63.2 Autism Spectrum Disorder & Intellectual Disabilities

ABFM Family Medicine Certification Study Guide Exam

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1 Chapter 1: Exam Structure, Blueprint & Clinical Decision-Making

1.1 Exam Blueprint, FMCLA vs. One-Day Exam & Board Scoring 1.2 Clinical Reasoning, Test-Taking Strategy & Ambiguity Management 1.3 Evidence-Based Medicine & Clinical Practice Guidelines in Primary Care

2 Chapter 2: Healthcare Systems, Practice Management & Quality

2.1 Practice Management, Billing, Coding & Documentation 2.2 Quality Improvement, Patient Safety & Diagnostic Stewardship 2.3 Interprofessional Team-Based Care & Care Coordination

3 Chapter 3: Ethics, Law, Biostatistics & Health Equity

3.1 Medical Ethics, Informed Consent & Surrogate Decision-Making 3.2 Biostatistics, Clinical Epidemiology & Diagnostic Test Interpretation 3.3 Social Determinants of Health, Health Equity & Cultural Humility 3.4 Physician Wellness, Burnout Prevention & Professionalism

4 Chapter 4: Lifestyle Counseling & Behavior Change

4.1 Alcohol Use Screening & Brief Intervention 4.2 Illicit Drug & Cannabis Counseling 4.3 Tobacco & Vaping Cessation Counseling

5 Chapter 5: Nutrition, Physical Activity & Chronic Disease Prevention

5.1 Dietary Counseling for Obesity & Chronic Disease Prevention 5.2 Exercise Prescription & Physical Activity Counseling 5.3 Genetic Risk Assessment & Family History Counseling

6 Chapter 6: Routine Adult Immunizations

6.1 ACIP Adult Respiratory Vaccines: Influenza, COVID-19, RSV & Pneumococcal 6.2 ACIP Adult Non-Respiratory Vaccines: Tdap, Shingrix, HPV & Hep B 6.3 Immunizations in Special Populations: Pregnancy, Asplenia & Immunocompromise

7 Chapter 7: Pediatric Health Maintenance & Surveillance

7.1 Newborn Examination & Early Postnatal Care 7.2 Well-Child Care, Developmental Surveillance & Milestones 7.3 Pediatric & Adolescent Screening: Vision, Hearing, Anemia & Lead 7.4 Pediatric Oral Health, Dental Screening & Fluoride

8 Chapter 8: Behavioral Health & Safety Screening

8.1 Primary Care Depression, Anxiety & Behavioral Health Screening 8.2 Domestic Violence, Intimate Partner Violence & Firearm Safety 8.3 Occupational Health & Recreational Safety Counseling

9 Chapter 9: Adult Preventive Screening: Cardiovascular & Metabolic

9.1 Cardiovascular Disease & Hypertension Screening 9.2 Type 2 Diabetes Screening & Prediabetes Risk Stratification 9.3 Abdominal Aortic Aneurysm & Osteoporosis Screening

10 Chapter 10: Adult Cancer Screening: Breast & Gynecologic

10.1 Breast Cancer Screening & Risk-Assessment 10.2 Cervical Cancer Screening & ASCCP Algorithms 10.3 Skin Cancer Clinical Assessment & Counseling

11 Chapter 11: Adult Cancer Screening: Colorectal, Lung & Prostate

11.1 Colorectal Cancer Screening Modalities & Intervals 11.2 Lung Cancer Screening with Low-Dose CT 11.3 Prostate Cancer Screening & Shared Decision-Making

12 Chapter 12: Sexual Health, Infectious Disease Screening & Contraception

12.1 Sexual Health Counseling & Risk-Reduction Strategies 12.2 STI Screening: Chlamydia, Gonorrhea, Syphilis & Trichomoniasis 12.3 Bloodborne Infectious Disease Screening: HIV & Hepatitis C

13 Chapter 13: Reproductive Life Planning, Lactation & Preoperative Care

13.1 Preconception Planning & Comprehensive Contraception Management 13.2 Lactation Support & Breastfeeding Counseling 13.3 Preoperative Medical Evaluation & Pre-Participation Sports Exam

14 Chapter 14: Emergent Cardiovascular Conditions

14.1 Acute Coronary Syndromes & Myocardial Infarction 14.2 Acute Chest Pain Risk Stratification & Triage 14.3 Acute or Critical Valvular Heart Emergencies

15 Chapter 15: Cardiac Arrhythmias, Heart Failure & Hypertensive Crises

15.1 Acute Atrial & Ventricular Arrhythmias 15.2 Acute Decompensated Heart Failure & Cardiogenic Shock 15.3 Hypertensive Emergency & Urgency Management

16 Chapter 16: Vascular & Thromboembolic Emergencies

16.1 Pulmonary Embolism & Deep Vein Thrombosis 16.2 Acute Aortic Syndromes & Peripheral Vascular Emergencies 16.3 Critical Limb Ischemia & Acute Arterial Occlusion

17 Chapter 17: Neurologic Emergencies: Stroke & Altered Consciousness

17.1 Acute Ischemic Stroke & Intracranial Hemorrhage 17.2 Syncope Evaluation & Status Epilepticus 17.3 Acute Delirium, Encephalopathy & Severe Confusion

18 Chapter 18: Neurologic Trauma & Acute Cranial Emergencies

18.1 Concussion, Moderate-to-Severe TBI & Intracranial Injury 18.2 Thunderclap & Acute Severe Secondary Headaches 18.3 Acute Ophthalmologic Emergencies

19 Chapter 19: Acute Abdominal, Pelvic & Gastrointestinal Emergencies

19.1 Acute Abdominal & Pelvic Pain Triage 19.2 Upper & Lower Gastrointestinal Bleeding 19.3 Acute Hepatic Failure, Cholangitis & Severe Jaundice

20 Chapter 20: Acute Pulmonary & Airway Emergencies

20.1 Acute Hypoxic Respiratory Failure & ARDS 20.2 Severe Community-Acquired Pneumonia & Empyema 20.3 Acute Severe Epistaxis & Airway Obstruction

21 Chapter 21: Acute Traumatic Injuries & Wound Care

21.1 Major Trauma Resuscitation & Initial Assessment 21.2 Burn Assessment, Inhalation Injury & Resuscitation 21.3 Laceration Management, Complex Wounds & Animal Bites

22 Chapter 22: Acute Orthopedic & Musculoskeletal Emergencies

22.1 Acute Ambulatory Fractures & Initial Splinting 22.2 Compartment Syndrome & Major Orthopedic Trauma 22.3 Septic Arthritis & Acute Microcrystalline Crises

23 Chapter 23: Severe Infections, Sepsis & Systemic Emergencies

23.1 Sepsis, Septic Shock & Initial Fluid Resuscitation 23.2 Necrotizing Soft Tissue Infections & Severe CNS Infections 23.3 Anaphylaxis Diagnosis, Epinephrine Dosing & Airway Protection

24 Chapter 24: Metabolic, Endocrine & Electrolyte Emergencies

24.1 Diabetic Ketoacidosis & Hyperosmolar Hyperglycemic State 24.2 Critical Electrolyte Emergencies: Dyskalemias & Dysnatremias 24.3 Severe Calcium Abnormalities & Acute Adrenal Crisis

25 Chapter 25: Hematologic, Urologic & Dental Emergencies

25.1 Severe Symptomatic Anemias & Coagulopathic Emergencies 25.2 Testicular Torsion, Priapism & Acute Urinary Retention 25.3 Urgent Odontogenic Infections & Dental Trauma

26 Chapter 26: Psychiatric, Behavioral & Obstetric/Gynecologic Emergencies

26.1 Suicidal Ideation, Acute Agitation & Behavioral Emergencies 26.2 Acute Physical & Sexual Assault Care 26.3 Life-Threatening Vaginal Bleeding & Ectopic Pregnancy 26.4 Environmental Heat Stroke & Severe Hypothermia

27 Chapter 27: Acute Head, Neck & Neurologic Symptoms

27.1 Primary Acute Headaches: Migraine, Tension & Cluster 27.2 Concussion & Minor Closed Head Injury Evaluation 27.3 Transient Ischemic Attack Evaluation & ABCD2 Risk Scoring

28 Chapter 28: Acute Cranial Nerves, Hearing & Sensory Symptoms

28.1 Peripheral Neuropathies: Bell's Palsy, Carpal Tunnel & Radiculopathy 28.2 Acute Tinnitus, Sudden Sensorineural Hearing Loss & Cerumen Impaction 28.3 Acute Dizziness, Benign Paroxysmal Positional Vertigo & Vestibular Neuritis

29 Chapter 29: Acute Upper Respiratory Tract Infections

29.1 Acute Viral Rhinosinusitis vs. Bacterial Rhinosinusitis 29.2 Acute Pharyngitis: Group A Streptococcus & Centor Criteria 29.3 Acute Otitis Media, Otitis Externa & Serous Effusion

30 Chapter 30: Acute Lower Respiratory Infections & Cough

30.1 Influenza, COVID-19 & Viral Respiratory Syndromes 30.2 Acute Bronchitis & Lower Respiratory Tract Infections 30.3 Ambulatory Community-Acquired Pneumonia

31 Chapter 31: Allergic, Nasal & Non-Infectious Pulmonary Conditions

31.1 Allergic Rhinitis & Acute Non-Anaphylactic Allergic Reactions 31.2 Acute Dyspnea in Ambulatory Care 31.3 Interstitial Lung Diseases & Sarcoidosis Presentation

32 Chapter 32: Acute Chest, Cardiac & Vascular Symptoms

32.1 Palpitations Evaluation & Arrhythmia Triage in Primary Care 32.2 Deep Vein Thrombosis & Superficial Thrombophlebitis 32.3 Ambulatory Hypotension & Orthostasis Evaluation

33 Chapter 33: Acute Upper Gastrointestinal Conditions

33.1 Peptic Ulcer Disease & Gastritis 33.2 Dysphagia, Esophagitis & Acute Esophageal Disorders 33.3 Acute Nausea, Vomiting & Foodborne Illness

34 Chapter 34: Acute Lower Gastrointestinal Conditions

34.1 Acute Infectious Diarrhea & Gastroenteritis 34.2 Acute Constipation & Functional Bowel Changes 34.3 Ano-Rectal Disorders: Hemorrhoids, Fissures, Abscesses & Pruritus Ani

35 Chapter 35: Inflammatory, Functional & Malabsorptive GI Disorders

35.1 Acute Flares of Inflammatory Bowel Disease 35.2 Irritable Bowel Syndrome: Diagnosis, Subtyping & Management 35.3 Celiac Disease & Malabsorption Syndromes

36 Chapter 36: Acute Abdominal, Hepatic & Biliary Disorders

36.1 Ambulatory Abdominal & Pelvic Pain Triage 36.2 Acute Cholecystitis, Biliary Colic & Pancreatitis 36.3 Acute Liver Injury & Viral Hepatitis

37 Chapter 37: Acute Abdominal Wall, Hernias & Dental Conditions

37.1 Abdominal Wall, Inguinal & Ventral Hernias 37.2 Acute Dental Pain, Odontogenic Abscess & Aphthous Ulcers 37.3 Acute Edema: Unilateral vs. Bilateral Diagnostic Evaluation

38 Chapter 38: Acute Infectious Dermatoses

38.1 Bacterial Skin Infections: Impetigo, Cellulitis & Cutaneous Abscesses 38.2 Fungal Skin Infections: Tinea Corporis, Cruris, Pedis & Onychomycosis 38.3 Viral Cutaneous Infections: Herpes Simplex, Zoster & Molluscum Contagiosum

39 Chapter 39: Inflammatory, Allergic & Autoimmune Dermatoses

39.1 Atopic Dermatitis, Contact Dermatitis & Eczematous Flares 39.2 Non-Infectious Rashes: Urticaria, Drug Eruptions & Erythema Multiforme 39.3 Cutaneous Malignancies & Premalignant Lesions: AK, BCC, SCC & Melanoma

40 Chapter 40: Acute Shoulder, Elbow & Upper Extremity Injuries

40.1 Rotator Cuff Pathology, Tendinopathy & Shoulder Impingement 40.2 Lateral & Medial Epicondylitis, Olecranon Bursitis & Elbow Sprains 40.3 Wrist & Hand Soft-Tissue Injuries: De Quervain, TFCC & Finger Sprains

41 Chapter 41: Acute Knee, Ankle & Lower Extremity Injuries

41.1 Meniscal Tears, Ligamentous Knee Injuries & Patellofemoral Pain 41.2 Ankle Sprains, Ottawa Ankle Rules & Achilles Tendinopathy 41.3 Plantar Fasciitis, Shin Splints & Overuse Syndromes

42 Chapter 42: Acute Ambulatory Fractures & Dislocations

42.1 Distal Radius, Scaphoid & Common Upper Extremity Fractures 42.2 Metatarsal, Clavicle & Common Lower Extremity Fractures 42.3 Joint Dislocation Management: Nursemaid's Elbow & Shoulder Subluxation

43 Chapter 43: Acute Axial Musculoskeletal Pain & Falls

43.1 Acute Low Back Pain: Red Flags, Strain & Disc Herniation 43.2 Acute Cervical Strain, Whiplash & Axial Neck Pain 43.3 Evaluation of Falls in Ambulatory & Older Patients

44 Chapter 44: Acute Inflammatory Arthropathies & Generalized Pain

44.1 Acute Inflammatory Arthritis & Spondyloarthropathies 44.2 Myalgias, Rhabdomyolysis & Post-Viral Pain Syndromes 44.3 Acute Non-Headache Pain Management Strategies

45 Chapter 45: Acute Renal, Urinary & Genitourinary Conditions

45.1 Uncomplicated UTI, Pyelonephritis & Acute Urethritis 45.2 Hematuria Workup & Glomerulonephritis 45.3 Nephrolithiasis & Acute Urinary Tract Obstruction

46 Chapter 46: Acute Male Genitourinary & Prostatic Conditions

46.1 Acute Prostatitis, Epididymitis & Orchitis 46.2 Acute Scrotal Pain: Torsion vs Appendage, BPH & Male Genital Emergencies 46.3 Acute Urinary Retention & Incontinence Evaluation

47 Chapter 47: Acute Women's Health & Early Pregnancy Care

47.1 Early Pregnancy Diagnosis, Dating & Initial Complications 47.2 Abnormal Uterine Bleeding & Acute Menstrual Disorders 47.3 Premenstrual Syndrome & Premenstrual Dysphoric Disorder

48 Chapter 48: Breast Disorders, STIs & Pediatric Elimination

48.1 Palpable Breast Mass, Mastitis & Nipple Discharge 48.2 Sexually Transmitted Infections: Diagnosis, Staging & CDC Guidelines 48.3 Pediatric Enuresis & Encopresis

49 Chapter 49: Systemic Signs, Metabolic Dysregulation & Miscellaneous Infections

49.1 Acute Fever, Sepsis Screening & FUO in Primary Care 49.2 Acute Hyperglycemia & Symptomatic Hypoglycemia 49.3 Electrolyte Abnormalities: Mild-to-Moderate Disturbances 49.4 Vector-Borne, Tick-Borne & Rickettsial Illnesses

50 Chapter 50: Chronic Cardiovascular Diseases: Hypertension & Ischemia

50.1 Essential Hypertension Management: 2025 AHA/ACC Guideline & JNC Strategies 50.2 Chronic Coronary Artery Disease & Post-MI Secondary Prevention 50.3 Chronic Heart Failure: HFrEF, HFpEF & Quadruple GDMT

51 Chapter 51: Chronic Vascular, Valvular & Dyslipidemic Diseases

51.1 Peripheral Arterial Disease & Claudication 51.2 Chronic Valvular Heart Disease & Murmur Evaluation 51.3 Lipid Disorders & ASCVD Risk-Based Statin Therapy

52 Chapter 52: Chronic Respiratory Diseases: Asthma & COPD

52.1 Chronic Asthma Management: GINA Stepwise SMART Therapy 52.2 Chronic Obstructive Pulmonary Disease: GOLD Recommendations 52.3 Solitary Pulmonary Nodule Evaluation & Fleischner Society Criteria

53 Chapter 53: Chronic Metabolic Diseases: Diabetes Mellitus

53.1 Type 2 Diabetes Management: ADA Pharmacotherapy Algorithms 53.2 Type 1 Diabetes: Basal-Bolus Insulin, CGMs & Diabetic Complications 53.3 Diabetic Microvascular & Macrovascular Disease Surveillance

54 Chapter 54: Obesity, Nutrition & Metabolic Bone Diseases

54.1 Medical & Behavioral Management of Obesity & Incretin Mimetics 54.2 Osteoporosis & Metabolic Bone Disease: DEXA, FRAX & Antiresorptives 54.3 Nutritional Deficiencies: Vitamin D, B12, Iron & Malnutrition

55 Chapter 55: Chronic Endocrine Disorders

55.1 Primary & Subclinical Hypothyroidism, Hyperthyroidism & Nodules 55.2 Adrenal Disorders: Addison's Disease & Cushing's Syndrome 55.3 Hypercalcemia, Hyperparathyroidism & Pituitary Disorders

56 Chapter 56: Chronic Kidney Disease & Venous Disorders

56.1 Chronic Kidney Disease: KDIGO Staging & Renoprotective Therapy 56.2 Chronic Venous Insufficiency, Stasis Dermatitis & Lymphedema 56.3 Chronic Electrolyte & Acid-Base Management in CKD

57 Chapter 57: Chronic Gastrointestinal & Hepatic Diseases

57.1 Gastroesophageal Reflux Disease, Barrett's Esophagus & Dyspepsia 57.2 Chronic Liver Disease: MASLD/NAFLD, Cirrhosis & Portal Hypertension 57.3 Viral Hepatitis B & C: Long-Term Monitoring & DAA Therapy

58 Chapter 58: Colorectal Surveillance & Chronic Pancreaticobiliary Care

58.1 Post-Polypectomy Colorectal Polyp Surveillance Guidelines 58.2 Chronic Pancreatitis & Exocrine Pancreatic Insufficiency 58.3 Chronic Nausea, Gastroparesis & Functional GI Disorders

59 Chapter 59: Chronic Musculoskeletal & Rheumatologic Disorders

59.1 Osteoarthritis: Hip, Knee & Hand Management 59.2 Spinal Conditions: Spinal Stenosis, Spondylolisthesis & Compression Fractures 59.3 Chronic Myopathies & Fibromyalgia Syndrome

60 Chapter 60: Chronic Neurologic & Neurodegenerative Disorders

60.1 Dementia: Alzheimer's, Vascular & Lewy Body Disease 60.2 Parkinson's Disease & Essential Tremor 60.3 Epilepsy: Chronic Antiseizure Medications & Post-Stroke Care

61 Chapter 61: Chronic Peripheral Nerves, Pain & Sensory Disorders

61.1 Diabetic & Chronic Peripheral Neuropathies 61.2 Chronic Pain Syndromes & Chronic Daily Headaches 61.3 Chronic Tinnitus, Presbycusis & Persistent Dizziness

62 Chapter 62: Chronic Psychiatric Disorders

62.1 Major Depressive Disorder & Generalized Anxiety Disorder 62.2 Bipolar Disorder: Maintenance Pharmacotherapy & Lithium Monitoring 62.3 Adult & Pediatric Attention-Deficit/Hyperactivity Disorder

63 Chapter 63: Chronic Behavioral Health & Neurodevelopmental Conditions

63.1 Chronic Behavioral Conditions: PTSD, OCD & Somatization 63.2 Autism Spectrum Disorder & Intellectual Disabilities 63.3 Eating Disorders: Anorexia Nervosa, Bulimia & Binge Eating

64 Chapter 64: Chronic Substance Use Disorders & Tobacco Cessation

64.1 Alcohol Use Disorder: Pharmacotherapy & Relapse Prevention 64.2 Opioid & Stimulant Use Disorders: MOUD & Harm Reduction 64.3 Longitudinal Tobacco Cessation Pharmacotherapy

65 Chapter 65: Chronic Dermatologic Conditions

65.1 Acne Vulgaris, Rosacea & Seborrheic Dermatitis 65.2 Chronic Plaque Psoriasis & Biologic Therapies 65.3 Chronic Eczema, Hidradenitis Suppurativa & Cutaneous Lupus

66 Chapter 66: Chronic Reproductive, Infectious & Geriatric Special Care

66.1 Chronic Menstrual Disorders, Infertility & Sexual Dysfunction 66.2 Menopause Management & Hormone Replacement Therapy 66.3 Chronic HIV Infection Management & Primary Care Integration 66.4 Gender-Affirming Primary Care & Hormone Therapy 66.5 Advance Care Planning, Palliative Care & End-of-Life Symptom Control

67 Chapter 67: Continuity Care: Sleep, Fatigue, Cancer, Pregnancy & the Adult Preventive Visit

67.1 Chronic Insomnia & Obstructive Sleep Apnea 67.2 Chronic Malaise, Fatigue & ME/CFS 67.3 Primary Care During Cancer Treatment & Survivorship 67.4 Routine Prenatal Care & Longitudinal Pregnancy Management 67.5 The Periodic Adult Health Examination & Medicare Annual Wellness Visit

63.2 Autism Spectrum Disorder & Intellectual Disabilities

Key Takeaways Explain This Topic AI

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by persistent deficits across two core DSM-5 domains: 1) social communication and social interaction, and 2) restricted, repetitive patterns of behavior, interests, or activities, with symptoms present in the early developmental period causing significant functional impairment.

The American Academy of Pediatrics (AAP) recommends continuous developmental surveillance at every well-child visit and dedicated universal standardized ASD screening at 18 months AND 24 months of age using the M-CHAT-R/F; high-risk scores (8-20) mandate immediate direct referral for comprehensive multidisciplinary evaluation and early intervention without a secondary follow-up interview.

Critical early red flags for ASD include lack of warm smiles by 6 months, no back-and-forth sharing of sounds/expressions by 9 months, no gestures (pointing, waving) by 12 months, no single words by 16 months, no two-word phrases by 24 months, and ANY loss of previously acquired speech or social skills at any age (regression occurs in 20-30%).

Early intensive behavioral intervention (Applied Behavior Analysis [ABA]) combined with speech and occupational therapy produces substantial cognitive and communicative improvements; pharmacotherapy does not treat core social deficits but risperidone (ages 5-16) and aripiprazole (ages 6-17) are FDA-approved for severe irritability, aggression, and self-injurious behavior, requiring routine metabolic monitoring.

Adults with intellectual disabilities face severe health disparities and high rates of 'diagnostic overshadowing'—the clinical error of attributing new behavioral agitation to baseline cognitive deficits rather than investigating occult physical illness (dental abscess, fecal impaction, urinary tract infection, occult fracture).

Last updated: September 2026

Autism Spectrum Disorder (ASD)

Autism Spectrum Disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized by persistent impairments in social communication and interaction paired with restricted, repetitive patterns of behavior, interests, or sensory activities. In the United States, ASD affects approximately 1 in 36 children, with a male-to-female ratio of approximately 4:1. However, females with ASD are frequently diagnosed later in life or overlooked entirely due to higher social motivation and advanced behavioral camouflaging ('masking').

Neurobiology & Etiology

The etiology of ASD is complex and predominantly genetic, with heritability estimates exceeding 80%:

Polygenic Architecture : Hundreds of common and rare genetic loci converge on pathways governing synaptogenesis, dendritic spine architecture, neuronal migration, and synaptic plasticity .

Brain Growth Trajectory : A subset of children with ASD (15-20%) exhibit abnormal early brain growth, characterized by accelerated head circumference expansion and macrocephaly between 6 and 14 months of age, followed by premature deceleration of brain growth in later childhood.

Neural Connectivity : Functional neuroimaging demonstrates local hyper-connectivity within isolated cortical circuits paired with long-range hypo-connectivity between distributed brain networks (e.g., fronto-striatal and fronto-temporal tracts), impeding complex social cognition, executive processing, and multisensory integration.

DSM-5 Diagnostic Criteria for ASD

A formal DSM-5 diagnosis requires persistent deficits across both core domains (Criterion A and Criterion B) : DSM-5 DIAGNOSTIC CRITERIA FOR ASD

• Domain & Criteria Mandatory Requirements & Clinical Manifestations
• ══════════════════════════════════════════════════════════════════════════════════════════════════════
• Criterion A Persistent deficits in social communication and social interaction

(Social Communication across multiple contexts (MUST MEET ALL 3):

& Interaction) 1. Deficits in social-emotional reciprocity:

• Abnormal social approach and failure of normal back-and-forth conversation.

• Reduced sharing of interests, emotions, or affect.

• Failure to initiate or respond to social interactions.

2. Deficits in nonverbal communicative behaviors:

• Poorly integrated verbal and nonverbal communication.

• Abnormalities in eye contact, body language, or deficits in understanding gestures.

• Total absence of facial expressions or nonverbal gestures.

3. Deficits in developing, maintaining, and understanding relationships:

• Difficulties adjusting behavior to suit diverse social contexts.

• Difficulties in sharing imaginative play or making friends.

• Absence of interest in peers.

• ──────────────────────────────────────────────────────────────────────────────────────────────────────
• Criterion B Restricted, repetitive patterns of behavior, interests, or activities

(Restricted / Repetitive (MUST MEET AT LEAST 2 OF THE FOLLOWING 4):

Behaviors & Sensory) 1. Stereotyped or repetitive motor movements, use of objects, or speech:

• Hand flapping, finger flicking, body rocking, spinning.

• Lining up toys, flipping objects repetitively.

• Echolalia (immediate or delayed), idiosyncratic phrases.

2. Insistence on sameness, inflexible adherence to routines, or ritualized patterns:

• Extreme distress at small changes in routine or environment.

• Difficulties with transitions; rigid thinking patterns.

• Ritualized greeting patterns, needing to take exact same route or eat same food.

3. Highly restricted, fixated interests abnormal in intensity or focus:

• Strong attachment to or preoccupation with unusual objects (e.g., vacuum cleaners).

• Excessively circumscribed or perseverative special interests.

4. Hyper- or hyporeactivity to sensory input or unusual sensory interests:

• Apparent indifference to pain or extreme temperatures.

• Adverse, extreme reactions to specific sounds, textures, or smells.

• Excessive smelling or touching of objects; visual fascination with lights/spinners.

• ──────────────────────────────────────────────────────────────────────────────────────────────────────
• Criterion C Symptoms must be present in the early developmental period (though may

(Developmental Timing) manifest fully later when social demands exceed capacities or masked by learned strategies).

• ──────────────────────────────────────────────────────────────────────────────────────────────────────
• Criterion D Symptoms cause clinically significant impairment in social, occupational,

(Functional Impairment) or other vital areas of current functioning.

• ──────────────────────────────────────────────────────────────────────────────────────────────────────
• Criterion E Disturbances are not better explained by intellectual disability or global

(Exclusion / Comorbidity) developmental delay (note: ID and ASD frequently co-occur).

• ══════════════════════════════════════════════════════════════════════════════════════════════════════
• Severity Specifiers for ASD

Severity is classified separately for Social Communication and Restricted/Repetitive Behaviors:

Level 1: 'Requiring support' : Noticeable impairments without supports; difficulty initiating social interactions; atypical or unsuccessful responses to social overtures; ritualized inflexibility interferes with functioning in one or more contexts.

Level 2: 'Requiring substantial support' : Marked deficits in verbal and nonverbal social communication; social impairments apparent even with supports; limited initiation; simple sentences; distress or difficulty coping with change.

Level 3: 'Requiring very substantial support' : Severe deficits in verbal and nonverbal skills causing severe functional impairment; very few words of intelligible speech; minimal response to social overtures; extreme difficulty coping with change; repetitive behaviors severely interfere with daily life.

Developmental Surveillance & Universal Screening (AAP Guidelines)

The American Academy of Pediatrics (AAP) establishes explicit guidelines separating continuous developmental surveillance from standardized screening:

Continuous Developmental Surveillance : Recommended at every well-child encounter from birth through adolescence, including eliciting parental concerns, documenting developmental milestones, and clinical observation.

General Standardized Developmental Screening : Administered using validated tools (e.g., Ages & Stages Questionnaires [ASQ-3], Parents' Evaluation of Developmental Status [PEDS]) at 9, 18, and 30 months of age .

Dedicated Universal ASD Screening : Administered to all children at 18 months AND 24 months of age (and at any visit when a parent or clinician raises concerns). THE M-CHAT-R/F SCREENING & TRIAGE ALGORITHM

• Total Score Range Risk Stratification Immediate Clinical Action Required
• ══════════════════════════════════════════════════════════════════════════════════════════════════════

Score 0 - 2 Low Risk • Negative screen.

• If child is <24 months, rescreen at 24-month well-child visit.

• Continue routine developmental surveillance.

──────────────────────────────────────────────────────────────────────────────────────────────────────

Score 3 - 7 Medium Risk • Administer the structured M-CHAT-R/F Follow-Up Interview.

• If Follow-Up score remains ≥2: Positive screen -> Refer for

comprehensive evaluation & Part C early intervention.

• If Follow-Up score is 0-1: Screen negative -> Routine surveillance.

──────────────────────────────────────────────────────────────────────────────────────────────────────

Score 8 - 20 High Risk • Screen HIGH POSITIVE.

• BYPASS the Follow-Up Interview!

• IMMEDIATELY refer for comprehensive multidisciplinary
• developmental evaluation AND refer directly to state-funded

Part C Early Intervention services.

• ══════════════════════════════════════════════════════════════════════════════════════════════════════
• Critical Early Red Flags for ASD ('Rules of Thumb')

Family physicians must recognize milestone absences that warrant prompt diagnostic referral rather than passive 'wait-and-see' reassurance:

By 6 Months : No social smiles or warm, joyful facial expressions directed at caregivers; lack of sustained eye contact.

By 9 Months : No back-and-forth sharing of vocal sounds, smiles, laughter, or facial expressions.

By 12 Months : Lack of reciprocal babbling; failure to respond to name (often mistaken for deafness); absence of communicative gestures (pointing, showing, reaching, waving goodbye).

By 16 Months : Complete absence of spoken single words.

By 24 Months : Complete absence of spontaneous, meaningful two-word phrases (excluding immediate echolalia or rote repetition).

AT ANY AGE : ANY loss of previously acquired speech, babbling, or social engagement ! Developmental regression occurs in approximately 20% to 30% of children with ASD, typically between 15 and 24 months of age, and represents a red-flag indication for urgent multidisciplinary evaluation.

Comprehensive Diagnostic Evaluation Workup

When an infant or toddler screens positive or displays red flags, the family physician must coordinate a multidisciplinary evaluation:

Formal Audiology Evaluation : Mandatory standardized audiometry to exclude conductive or sensorineural hearing loss as a primary driver of language delay.

Multidisciplinary Developmental Assessment : Comprehensive evaluation utilizing gold-standard standardized diagnostic instruments (Autism Diagnostic Observation Schedule-2 [ADOS-2] and Autism Diagnostic Interview-Revised [ADI-R]) administered by a developmental pediatrician, child psychologist, or pediatric neurologist.

First-Line Genetic Testing : Chromosomal Microarray (CMA) and Fragile X DNA analysis ( FMR1 CGG trinucleotide repeat expansion) are recommended first-line investigations. Whole-exome sequencing (WES) is increasingly utilized if CMA is non-diagnostic.

Neurological & Metabolic Testing : Routine brain MRI and routine EEG are not recommended unless the child exhibits focal neurological deficits, microcephaly, macrocephaly, tuberous sclerosis stigmas (ash-leaf spots), or clinical unprovoked seizures.

• Evidence-Based Interventions for ASD
• 1. Non-Pharmacologic Early Intervention (First-Line Standard of Care)

Neuroplasticity is maximal in early childhood; early initiation of intensive behavioral and developmental therapies yields dramatic gains in IQ, language, and adaptive living scores:

Applied Behavior Analysis (ABA) : The gold-standard intensive behavioral therapy (typically 20-40 hours per week). ABA breaks complex communicative, social, and functional living skills down into discrete, manageable steps, utilizing systematic positive reinforcement to build adaptive behaviors and reduce maladaptive behaviors.

Speech and Language Therapy : Initiated early to develop pragmatic communication skills; for nonverbal children, early introduction of Augmentative and Alternative Communication (AAC) systems (e.g., Picture Exchange Communication System [PECS] or speech-generating tablet devices) fosters functional language and prevents behavioral frustration.

Occupational Therapy : Focuses on sensory integration therapies, fine motor coordination, and self-care activities of daily living.

Educational Support : Mandated federal support via the Individuals with Disabilities Education Act ( IDEA ): an Individualized Family Service Plan ( IFSP ) under Part C (birth to age 3) transitioning to an Individualized Education Program ( IEP ) under Part B (ages 3 to 21).

2. Pharmacotherapy for Target Symptoms in ASD

Important

Pharmacotherapy does NOT treat core social communication deficits or repetitive behaviors in ASD. Prescription medications are strictly reserved for severe, functionally impairing target symptoms refractory to behavioral interventions: extreme irritability, physical aggression, severe temper tantrums, and self-injurious behavior (SIB). FDA-APPROVED ATYPICAL ANTIPSYCHOTICS FOR ASD TARGET SYMPTOMS

• Agent FDA Age Range Initial & Target Dosing Key Adverse Effects & Monitoring
• ══════════════════════════════════════════════════════════════════════════════════════════════════════
• Risperidone Ages 5 - 16 Weight <20 kg: Start 0.25 mg/day • Severe weight gain & metabolic syndrome
• years Weight ≥20 kg: Start 0.5 mg/day • Hyperprolactinemia (galactorrhea, gynecomastia)
• Target: 1.0 - 2.5 mg/day • Somnolence, sedation, tremor
• (Max: 3.0 mg/day) • EPS and Tardive Dyskinesia risk
• ──────────────────────────────────────────────────────────────────────────────────────────────────────
• Aripiprazole Ages 6 - 17 Start: 2 mg orally daily • Weight gain (less than risperidone)
• years Titrate by 2-5 mg weekly • Akathisia (motor restlessness, agitation)
• Target: 5 - 10 mg/day • Somnolence, insomnia, nausea
• (Max: 15 mg/day) • EPS and Tardive Dyskinesia risk
• ══════════════════════════════════════════════════════════════════════════════════════════════════════

Mandatory Safety & Metabolic Monitoring Protocol :

Baseline : Body weight, height, BMI, blood pressure, fasting plasma glucose or HbA1c, and fasting lipid profile.

At 3 Months : Repeat BMI, blood pressure, fasting glucose, and fasting lipid panel.

Annually : Fasting glucose/HbA1c and lipid panel.

Every Encounter : Clinical surveillance for extrapyramidal symptoms (EPS), akathisia, and involuntary motor movements utilizing the Abnormal Involuntary Movement Scale (AIMS) .

Comorbid ADHD in ASD : Approximately 30-50% of children with ASD have comorbid ADHD. Stimulants (methylphenidate) and non-stimulants (guanfacine, atomoxetine) are effective; however, children with ASD experience higher rates of adverse effects (irritability, emotional lability, insomnia) from psychostimulants than neurotypical children, warranting cautious low-dose titration.

Intellectual Disability (Intellectual Developmental Disorder)

Intellectual Disability is a lifelong neurodevelopmental disorder defined by concurrent deficits in cognitive abilities and adaptive functioning with onset during the developmental period.

DSM-5 Diagnostic Criteria

Diagnosis requires meeting all three core criteria :

Deficits in Intellectual Functions : Reasoning, problem-solving, planning, abstract thinking, judgment, academic learning, and experiential learning. Confirmed through clinical evaluation and standardized, individualized cognitive testing yielding an IQ score of approximately 70 or below (representing ≥2 standard deviations below the population mean of 100, accounting for a 5-point measurement error margin: 65 to 75).

Deficits in Adaptive Functioning : Failure to meet developmental and sociocultural standards for personal independence and social responsibility. Without ongoing support, adaptive deficits limit functioning in one or more activities of daily life across three adaptive domains :

Conceptual Domain : Competence in language, reading, writing, mathematics, reasoning, knowledge, and memory.

Social Domain : Empathy, interpersonal communication, social judgment, friendship abilities, and awareness of others' thoughts and feelings.

Practical Domain : Self-management across life settings, including personal care, job responsibilities, money management, recreation, transportation, and organizing school or work tasks.

Developmental Onset : Onset of intellectual and adaptive deficits occurs during the developmental period (before age 18). ADAPTIVE FUNCTIONING SEVERITY TIERS IN INTELLECTUAL DISABILITY

• Severity Level Conceptual Domain Social Domain Practical Domain
• ══════════════════════════════════════════════════════════════════════════════════════════════════════════
• Mild Difficulties learning academic Immature social interactions; Independent personal care;
• (~85% of ID) skills (reading, math); abstract gullibility; risk of being requires support for complex

thinking impaired in adults. manipulated by peers. tasks (money, legal, taxes).

• ──────────────────────────────────────────────────────────────────────────────────────────────────
• Moderate Markedly behind peers; academic Simple spoken language; Can care for personal needs
• (~10% of ID) skills at elementary level; interprets social cues poorly; with extended teaching;

requires daily assistance. support needed for friendships. semi-independent group living.

• ──────────────────────────────────────────────────────────────────────────────────────────────────
• Severe Limited conceptual attainment; Spoken language very limited; Requires support for all
• (~3-5% of ID) little understanding of written communicates via single words daily living activities;

language or numeric concepts. or gestures; focused on here. cannot live independently.

• ──────────────────────────────────────────────────────────────────────────────────────────────────
• Profound Concepts involve physical world Very limited understanding of Dependent on caregivers for
• (~1-2% of ID) rather than symbolic processes; symbolic communication; all aspects of daily physical

co-occurring motor/sensory deficits. expresses desires nonverbally. care, health, and safety.

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Exam Pearl : Under DSM-5, the severity of Intellectual Disability is determined by the level of adaptive functioning , NOT by the IQ score, because adaptive functioning determines the actual level of environmental support required.

Etiologic Classifications

Genetic Etiologies :

Down Syndrome (Trisomy 21) : Most common genetic cause of ID. Associated with characteristic facies, hypotonia, congenital heart defects (atrioventricular septal defects), early-onset Alzheimer neuropathology by age 40, celiac disease, hypothyroidism, and atlantoaxial instability.

Fragile X Syndrome : Most common inherited cause of intellectual disability in males. Caused by an unstable CGG trinucleotide repeat expansion (>200 repeats) in the FMR1 gene on the X chromosome leading to transcriptional silencing. Phenotype includes long, narrow face, prominent jaw, large everted ears, joint hypermobility, macroorchidism post-puberty, and high rates of co-occurring ASD.

Rett Syndrome : X-linked dominant mutation in the MECP2 gene, primarily affecting females. Features normal early development followed by rapid regression of purposeful hand skills and expressive language, replaced by stereotypic hand-wringing or hand-washing movements , microcephaly, breathing irregularities, and ataxia.

Metabolic & Environmental Etiologies :

Inborn Errors of Metabolism : Phenylketonuria (PKU; screened at birth), galactosemia, Wilson disease.

Fetal Alcohol Spectrum Disorder (FASD) : Leading preventable cause of ID. Cardinal facial dysmorphisms: smooth philtrum, thin vermilion border of upper lip, short palpebral fissures, paired with microcephaly and severe behavioral deficits.

Congenital Infections (TORCH) : Cytomegalovirus (CMV; periventricular calcifications, sensorineural hearing loss), Toxoplasmosis (chorioretinitis, hydrocephalus, diffuse intracranial calcifications), Rubella, Congenital Syphilis.

Perinatal & Postnatal Insults : Hypoxic-ischemic encephalopathy, kernicterus, extreme prematurity, bacterial meningitis, traumatic brain injury, and chronic lead neurotoxicity.

• Primary Care Health Maintenance for Adults with Intellectual Disabilities
• 1. Communication & Legal Decision-Making Capacity

Address the patient directly using clear, concrete language, visual aids, and extra processing time, while also engaging caregivers or group home staff for collateral information.

Assess legal decision-making capacity. Differentiate between independent decision-making, supported decision-making agreements, healthcare power of attorney, and formal court-appointed legal guardianship . Consent for invasive procedures or pharmacotherapy must be obtained from the legally recognized surrogate if guardianship is documented.

2. Eliminating Cancer Screening Disparities

Adults with intellectual disabilities face pervasive health disparities and are frequently denied evidence-based preventive screenings:

Cervical Cancer Screening : Regular Pap smears and HPV testing must be maintained per USPSTF guidelines. Desensitization, pre-visit clinic tours, and gentle pelvic examinations (or sedation if strictly necessary) should be offered rather than arbitrarily omitting screening.

Colorectal Cancer Screening : Screening from ages 45 to 75 must be prioritized. If immobility or sensory defensiveness precludes colonoscopy preparation, non-invasive stool-based testing (FIT or stool DNA-FIT) should be deployed.

3. Dental Care & Bone Health

Dental Disease : High incidence of untreated periodontal disease, caries, and tooth loss due to poor manual dexterity, medication-induced xerostomia, and sensory aversion. Biannual specialized dental cleanings are required.

Bone Health : Markedly elevated risk of premature osteoporosis and fragility fractures driven by immobility, low dietary calcium/vitamin D, and chronic treatment with enzyme-inducing antiepileptic drugs (e.g., phenytoin, carbamazepine, phenobarbital) that induce CYP3A4 and accelerate 25-hydroxyvitamin D catabolism. Clinicians must monitor 25-OH vitamin D levels, optimize calcium supplementation, and obtain baseline DEXA scans in high-risk patients.

4. The Critical Danger of 'Diagnostic Overshadowing'

Caution

Diagnostic Overshadowing is the cognitive bias wherein a healthcare provider erroneously attributes new, emerging, or worsening behavioral symptoms (such as agitation, screaming, aggression, pacing, or self-injurious head-banging) to the patient's baseline intellectual disability or autism, rather than investigating an acute, treatable medical illness.

Individuals with severe cognitive and expressive communication deficits cannot verbalize pain. When experiencing acute physical distress, they express discomfort through behavioral agitation. Whenever an adult with intellectual disability presents with a sudden behavioral change, the family physician must perform a systematic physical examination and laboratory workup to rule out occult physical sources of pain before escalating behavioral medications:

Dental Abscess : Impacted third molars or periapical dental infection.

Severe Constipation / Fecal Impaction : Palpable lower-quadrant abdominal mass, stercoral ulceration.

Urinary Tract Infection (UTI) : Cystitis, pyelonephritis, urinary retention.

Gastroesophageal Reflux Disease (GERD) : Esophagitis, peptic ulceration (often presenting as mealtime aggression).

Occult Orthopedic Fractures : Undetected fall fractures (especially femoral neck or ribs).

Acute Otitis Media or Corneal Abrasion : Ear canal foreign body, cerumen impaction, eye scratching.

Loading diagram... Pediatric Autism Screening Algorithm and Diagnostic Overshadowing Pathway