Study guide
7.2 Mental, Substance Use, Injuries/Toxicology, and HIV-Related Conditions
Certified Clinical Documentation Specialist CCDS
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1 Introduction & Exam Overview
1.1 Current Exam Facts 1.2 Eligibility Pathways and the 2,000-Hour Year 1.3 Allowed Resources and Test-Day Rules 1.4 Recertification, Fees, and How This Guide Maps the Eight Domains
2 IPPS Foundations
2.1 How IPPS Works and How CMS Updates It 2.2 MS-DRG Assignment, Relative Weights, and Grouping 2.3 Provider and Clinical Staff Documentation Duties under IPPS
3 Severity, CMI, Medical Necessity, and Oversight
3.1 CC versus MCC Recognition and CC Exclusion Lists 3.2 Case Mix Index and Why CDI Tracks It 3.3 Two-Midnight Rule, Medical Necessity of Setting, and Principal Diagnosis 3.4 MAC, RAC, CERT, OIG, and Denial-Vulnerable Practices
4 Nervous and Respiratory System CDI
4.1 Nervous System Conditions for CDI 4.2 Acute and Chronic Respiratory Failure, ABGs, and Ventilation Support 4.3 Pneumonia, COPD, PE, Pleural Effusion, and Respiratory Infections
5 Circulatory, Digestive, Hepatobiliary, Musculoskeletal, and Skin CDI
5.1 Circulatory Disorders 5.2 Digestive and Hepatobiliary Disorders 5.3 Musculoskeletal and Skin
6 Endocrine, Nutrition, Kidney, and Hematologic CDI
6.1 Diabetes, Dehydration, and Obesity 6.2 Malnutrition Criteria, Severity, and Audit Risk 6.3 AKI, CKD Staging, UTI, and Urinary Stones 6.4 Anemia, Coagulation, Sickle Cell, Lymphoma, and Leukemia
7 Infectious Disease, Other MDCs, and Clinical Indicator Tools
7.1 Sepsis, Severe Sepsis, Postoperative and Other Infections 7.2 Mental, Substance Use, Injuries/Toxicology, and HIV-Related Conditions 7.3 Medications, Diagnostic Tests, and Abbreviations as Clinical Indicators
8 Health Record Elements and Query Triggers
8.1 Which Record Elements Support Diagnosis and Procedure Codes 8.2 Attending versus Radiologist, Pathologist, and Other Providers 8.3 When a Physician Query Is Warranted 8.4 When Queries Are Not Appropriate
9 Query Timing, Verbal Queries, Formats, and Clinical Indicators
9.1 Concurrent, Retrospective, Pre-Bill, and Prospective Timing 9.2 Verbal Queries and Required Documentation 9.3 Open-Ended, Multiple-Choice, and Yes/No 9.4 Clinical Indicators and How to Source Them
10 Compliant Query Practice and Clinical Validation
10.1 Compliant versus Leading and Other Noncompliant Queries 10.2 ACDIS/AHIMA 2026 Guidelines for Achieving a Compliant Query Practice 10.3 Clinical Validation and Diagnoses without Clinical Support
11 CDI Program Metrics
11.1 Productivity, Query Volume, and Provider Response Rates 11.2 CMI, CC/MCC Capture, and High-Frequency DRGs 11.3 SOI/ROM as CDI Program Performance Metrics
12 Physician Metrics, PEPPER, Forecasting, and Public Data
12.1 Measuring Physician Documentation Performance 12.2 PEPPER, Forecasting, Hospital Financial Data, and Public Reporting
13 CDI Roles, Coder Collaboration, and Physician Education
13.1 Roles and Responsibilities of the CDI Specialist 13.2 Coder Roles Working with a CDI Department 13.3 Physician Education Tools, Forms, and Presentations
14 Provider Communication and DRG Reconciliation
14.1 Non-Confrontational Communication and When Verbal Beats Written 14.2 Working DRG versus Final DRG Reconciliation
15 Official Guidelines, Principal Diagnosis, and Secondary Diagnosis
15.1 Official Guidelines, Cooperating Parties, Updates, and AHA Coding Clinic 15.2 Principal Diagnosis Selection 15.3 Secondary Diagnosis Reporting Criteria
16 Sequencing, Coding Conventions, and POA Indicators
16.1 Sequencing When Two Diagnoses Equally Meet PD; Working DRG with Multiple Diagnoses 16.2 Integral Signs/Symptoms, the With Convention, and Uncertain Diagnoses 16.3 Present-on-Admission Indicator Assignment and Payment Impact
17 Hospital-Acquired Conditions, Disposition, and ICD-10-PCS Essentials
17.1 CMS Hospital-Acquired Condition Payment Provision 17.2 Discharge Disposition, Transfer Payment, Principal Procedure, and ICD-10-PCS Essentials
18 Ethics, Privacy, and Leading Queries as Compliance Failures
18.1 ACDIS Code of Ethics and CDI Goals beyond Reimbursement 18.2 HIPAA, Minimum Necessary, and Record Confidentiality 18.3 Leading Queries as a Compliance Failure
19 DRG Creep, OIG Oversight, PEPPER, and the False Claims Act
19.1 DRG Compliance, DRG Creep, and the OIG Work Plan 19.2 PEPPER Compliance Risks and the False Claims Act
20 Mortality Index, Observed-to-Expected Ratios, and Quality Data Sources
20.1 Documentation Impact on Mortality Index (SOI/ROM) 20.2 Mortality Reviews and Observed-to-Expected Ratios 20.3 Abstracted versus Claims-Based Quality Data
21 CMS Quality Programs, PSIs, and Infection versus Complication Codes
21.1 HVBP, HAC Reduction Program, HRRP, 30-Day Mortality, and Hospital IQR 21.2 PSI 90 Components and PSIs beyond the Composite 21.3 Healthcare-Associated Infections versus Complication Codes
7.2 Mental, Substance Use, Injuries/Toxicology, and HIV-Related Conditions
Key Takeaways Explain This Topic AI
Psychosis, dementia, delirium, and encephalopathy are not interchangeable labels; query for type, acuity, and cause rather than swapping words to pursue an MCC
Alcohol intoxication is the acute effect of recent use; alcohol withdrawal, including withdrawal delirium, is a different diagnosis that may appear later in the same stay
Poisoning is improper use; an adverse effect is a correctly prescribed and properly administered drug; underdosing is taking less than prescribed and is never principal
HIV-positive status without related illness is Z21; once an HIV-related illness is documented, B20 is reported on every later encounter. DRG Expert lists which diagnoses are major related conditions in MDC 25
Functional quadriplegia is complete immobility from severe disability or frailty without neurologic paralysis and needs a provider diagnostic statement; nursing total-care scores are indicators, not codes
Last updated: September 2026
7.2 Mental, Substance Use, Injuries/Toxicology, and HIV-Related Conditions
Quick Answer: Do not treat psychosis , dementia , delirium , and encephalopathy as synonyms. Separate alcohol intoxication from alcohol withdrawal . Classify drug harm as poisoning (improper use), adverse effect (correct drug, correct administration), or underdosing (less than prescribed; never principal). For human immunodeficiency virus (HIV) , Z21 is asymptomatic status; B20 is HIV disease and, once an HIV-related illness has occurred, B20 is used on every later encounter. Use DRG Expert to see whether a documented condition is a major related condition in Major Diagnostic Category (MDC) 25 . Functional quadriplegia needs a provider statement of complete immobility from frailty or severe disability, not a nursing total-care row and not spinal tetraplegia.
This independent ExamFinch section helps inpatient CDI specialists study these other MDC topics for the CCDS exam. It is not an ACDIS product and does not claim ACDIS approval, review, or partnership.
Psychosis is unfinished documentation
Psychosis at the bedside is a family of presentations: schizophrenia and related disorders, bipolar disorder with psychotic features, major depression with psychotic features, substance-induced psychotic disorder, and perceptual disturbance in delirium. A nursing comment that the patient is psychotic is an indicator, not a diagnostic statement. Query for the type and, when substances or a medical cause are in play, the cause . Do not assign unspecified psychosis from a sitter order. Do not convert delirium with hallucinations into a primary psychotic disorder because an MCC looks attractive. The 2026 query standard still requires clinically relevant options, Other, please specify , and no reimbursement language. Yes/no may not introduce a new psychiatric diagnosis.
Dementia versus delirium versus encephalopathy
Dementia is a chronic, usually progressive baseline cognitive disorder (Alzheimer disease, vascular dementia, Lewy body disease, and other specified types). Capture type when the provider states it, and capture with behavioral disturbance only when that disturbance is documented and relevant this stay under Uniform Hospital Discharge Data Set (UHDDS) secondary-diagnosis rules (evaluation, treatment, extra monitoring, or extended length of stay). A copied problem-list line of dementia does not automatically meet UHDDS.
Delirium is an acute, fluctuating disturbance of attention and awareness. Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) scores, a sudden change from baseline, and a precipitant such as infection, hypoxia, or polypharmacy are indicators. Delirium can overlay dementia. That overlap is a query, not a silent swap.
Encephalopathy is a provider neurologic diagnosis of diffuse brain dysfunction. Type and cause matter (metabolic, toxic, hepatic, hypertensive, anoxic). Chapter 4 of this guide treats encephalopathy in depth. The trap in this cluster is using encephalopathy as a prettier word for delirium, or using delirium as a prettier word for dementia, in order to change severity. If the record mixes the terms, query. Do not relabel CAM-ICU-positive delirium as metabolic encephalopathy solely because metabolic encephalopathy can group as an MCC when it is documented, supported, and not inherent to the principal diagnosis.
Original scenario. Mr. L., 84, lives with documented Alzheimer disease. On hospital day two he is CAM-ICU positive, picking at lines, and oriented only to self after hyponatremia to 118 mEq/L. The intern writes worsening dementia. CDI should not upgrade chronic dementia into a new baseline. A nonleading query can ask whether the acute change is delirium, metabolic encephalopathy related to hyponatremia, expected fluctuation of known dementia without a separate acute diagnosis, or Other, please specify.
Alcohol: intoxication is not withdrawal
Alcohol intoxication is the acute effect of recent drinking: slurred speech, ataxia, a measurable ethanol level, and often trauma. Alcohol withdrawal is the syndrome that appears after cessation or reduction: tremor, tachycardia, hypertension, diaphoresis, Clinical Institute Withdrawal Assessment for Alcohol (CIWA) protocol, benzodiazepines, withdrawal seizures, or withdrawal delirium (delirium tremens). The same patient can arrive intoxicated and withdraw on day two. Those are sequential diagnoses, not synonyms. A problem list that says only ETOH is unfinished work.
Thiamine, folate, and a banana bag are nutritional-risk indicators. They do not by themselves establish Wernicke encephalopathy. Query if ophthalmoplegia, ataxia, and confusion are present and the provider has not named the diagnosis. Do not use a yes/no query that plants Wernicke from a vitamin order.
Poisoning versus adverse effect versus underdosing
ICD-10-CM categories T36–T50 are combination codes that include the substance and the intent. Do not code directly from the Table of Drugs and Chemicals; confirm in the Tabular List. No extra Chapter 20 external-cause code is required for these T-codes.
Construct What happened Coding implication
Adverse effect Drug correctly prescribed and properly administered Nature of the effect first (bleeding, delirium, renal failure), then the T-code with 5th or 6th character 5
Poisoning Overdose, wrong substance, wrong route, prescription or administration error, drug–alcohol interaction, or a nonprescribed drug interacting with a prescribed one T-code first with intent character (accidental, intentional self-harm, assault, undetermined), then manifestations. Unknown intent defaults to accidental ; undetermined only if the record says intent cannot be determined
Underdosing Taking less than prescribed, or stopping a prescribed drug on the patient’s own initiative T-code with 5th or 6th character 6 ; never principal . Code the relapsing condition that occasioned the stay. Add noncompliance or complication-of-care codes when intent is known
Toxic effect (T51–T65) Harmful nonmedicinal substance (alcohol as toxic effect when classified that way, carbon monoxide, pesticides) Toxic-effect code first, then manifestations, with intent
Original scenario. Ms. H. takes warfarin exactly as prescribed. She is admitted with hematemesis and an international normalized ratio of 9.2. This is an adverse effect pattern: the nature of the effect is the bleed, then the T-code for anticoagulant with character 5. It is not a poisoning because the drug was taken correctly. It is not underdosing.
Original scenario. Mr. J. takes extra oxycodone from a leftover bottle plus beer and is found unresponsive; naloxone reverses him. Interaction of a drug with alcohol is classified as poisoning . Intent still has to be documented or queried; do not invent intentional self-harm from a single overdose if the record is silent.
Original scenario. Ms. C. stops her furosemide because she was traveling, then presents in acute heart-failure exacerbation. Underdosing is additional, never principal. The heart-failure exacerbation is the condition that occasioned the admission if that is what the record supports.
HIV: sequencing, Z21 versus B20, and DRG Expert grouping
Provider documentation that the patient is HIV positive or has an HIV-related illness is sufficient; serology is not required to “confirm” the statement. Z21, Asymptomatic human immunodeficiency virus infection status , applies when the record says HIV positive, known HIV, or HIV test positive without symptoms or HIV-related illness. Do not use Z21 if the term AIDS or HIV disease is used, or if the patient is treated for any HIV-related illness. B20, Human immunodeficiency virus disease , is assigned in those situations. Once an HIV-related illness has developed, B20 is assigned on every subsequent encounter ; the patient does not return to Z21 or to R75 (inconclusive serology). Antiretroviral medication does not by itself convert Z21 into B20; the Official Guidelines distinguish HIV disease or AIDS on antiretrovirals (B20) from HIV-positive status on antiretrovirals without additional documentation of disease (Z21).
If the patient is admitted for an HIV-related condition, B20 is principal , followed by codes for the related conditions (with a published exception for infection-associated hemolytic-uremic syndrome, which is sequenced before B20). If the patient is admitted for an unrelated condition such as a traumatic injury, the unrelated condition is principal and B20 is secondary. New versus old diagnosis does not change that sequencing logic.
Major related condition is a Medicare Severity Diagnosis Related Group (MS-DRG) grouping concept, not an Official Guidelines synonym for MCC. CMS places HIV cases in MDC 25 . The Definitions Manual and DRG Expert (an allowed optional resource on the CCDS exam) list which diagnoses count as HIV with major related condition versus HIV with or without other related condition . Opportunistic infections such as pneumocystosis appear on the major-related lists; many other documented problems do not. Look the condition up. Do not memorize an unpublished relative weight, and do not invent a homemade major-related list. CDI value is making sure the provider has actually diagnosed the related condition that the grouper can see—not dropping pneumocystosis in from a historical CD4 nadir.
Trauma documentation
When injury occasioned the admission, the nature of injury is the principal-diagnosis conversation: site, laterality, open versus closed, displacement when documented, intracranial injury versus concussion, and loss of consciousness if the provider states it. Radiology of a possible occult fracture is an indicator until the provider indicates clinical significance (see section 7.3). Glasgow Coma Scale values are indicators and, when reported, follow Official Guidelines for coma-scale use; do not report unspecified coma for a medically induced or purely sedated state.
Falls and trauma that are not present on admission can intersect the HAC payment-provision category for falls and trauma (fractures, dislocations, intracranial injury, crushing, burns, and other listed injuries). That is the claim-level payment provision. It is not the HAC Reduction Program, and it is not PSI-90 by another name. POA for an injury that occurred before the inpatient order, including in the emergency department, is Y .
Functional versus neurologic quadriplegia
Functional quadriplegia (ICD-10-CM R53.2 ) is complete immobility due to severe physical disability or frailty. The Tabular List’s applicable language is complete immobility from severe disability or frailty—not paralysis from a spinal-cord or brain lesion. Neurologic quadriplegia or tetraplegia (category G82 ) is a different diagnosis. The Official Guidelines formerly had a separate functional-quadriplegia paragraph; that guideline was deleted effective October 1, 2017 . Current teaching therefore follows the Tabular definition plus provider documentation, not a deleted guideline.
Nursing rows that say total care, a Barthel index of zero, or a high Braden risk score are indicators . They are not a diagnostic statement. Do not assign functional quadriplegia from an activities-of-daily-living flowsheet. Do not assign neurologic quadriplegia because someone wrote quad in a wound note for a contracted, bedbound patient without spinal injury. Functional quadriplegia has often grouped as an MCC when reported as a secondary diagnosis; verify the current IPPS CC/MCC assignment in DRG Expert . Developmental disorders (for example, intellectual disability or autism spectrum conditions documented as currently affecting care) sit on the same MDC 19 list as psychosis and dementia. They are reportable when they meet UHDDS secondary-diagnosis criteria for this encounter—evaluation, treatment, monitoring, or increased nursing care—not merely because they appear on an old problem list. Query only if the record is unclear whether the condition is active this stay.
Never query with MCC language. First-time capture uses multiple-choice, including an option that the immobility is explained by another documented condition without functional quadriplegia, plus Other, please specify.
Loading diagram... HIV status, sequencing, and MDC 25 lookup
Putting the toxicology and HIV queries together
Source every indicator: ethanol level, CIWA score, medication administration record, INR, naloxone, CD4 if obtained, antiretroviral list, injury mechanism, and nursing mobility scores. Offer only options the chart can support. Do not offer intentional self-harm when the record describes a clearly accidental extra dose. Do not offer B20 when the only language is HIV positive, on antiretrovirals, no prior opportunistic illness. Do not offer functional quadriplegia for a patient who is walking in the hall. Keep DRG, MCC, and HAC words out of the query. If you are validating a diagnosis already written that looks unsupported—severe malnutrition is the usual example, but the same pattern applies to functional quadriplegia or pneumocystosis copied from 2018—multiple-choice with confirmed with support, ruled out, no longer valid, and an alternative diagnosis is the 2026-preferred clinical-validation pattern.