HIV Associated dementia/ AIDS dementia complex

Edson MutandwaMBBS IV

Presentation outlineIntroductionEpidemiologyPathophysiologyRisk factorsClinical featuresDiagnostic criteriaDifferential diagnosisWork-upprognosismanagement

Introduction

HIV associated dementia is one of the HIV-associated neurocognitive disorders

The term AIDS dementia complex was introduced by Navia and colleagues in 1986 to describe a unique constellation of neurobehavioral finding.

EpidemiologyThe risk of severe neurocognitive disorders in patients

with HIV is 1 in 1000The annual incidence of HIV dementia in the Western

world prior to HAART was 7%, with a cumulative risk of 5-20%.With HAART, the incidence of HIV dementia started declining, but it has begun to increase again

PathophysiologyThe mechanism by which HIV infection of the CNS leads

to neurocognitive disorders is likely multifactorial and is the subject of intense research

It has been proposed that HIV enters the CNS via infected monocytes that traverse the blood-brain barrier to replenish perivascular macrophages (Trojan horse mechanism)

PathophysiologyCellular proteins-secretion of chemokines,

proinflammatory cytokines, nitrous oxide, and other neurotoxic factor

HIV proteins (virotoxins)-Damage to neurons may occur through the actions of specific HIV proteins, including gp120, gp41, Tat, Nef, Vpr, and Rev

Autoimmune disease-CNS damage may occur by humoral immune mechanisms, as evidenced by the presence of anti-CNS antibodies in AIDS patients with dementia but not in those without dementia

Risk factorslow weightAnemiaconstitutional symptomslow CD4+ counthigh plasma HIV-RNA loadFemale genderOld age (>50)

Clinical featuressubstantial memory deficitsnegative personality mood changesimpaired executive functioningpoor attention and concentrationmental slowingapathy

Diagnostic criteriaNo other etiology of dementia and must not have the confounding effect of substance use or psychiatric illness. Criteria for the diagnosis of HAD included cognitive

deficits in 2 or more cognitive domains that cause impairment in activities of daily living (ADL) and an abnormality in either motor or neurobehavioral function

Diagnostic criteriaThe domains includedCognitionLanguageAttentionexecutive functionMemoryspeed of information processingperceptual and motor skills

Differential diagnosisAlzheimer DiseaseFrontal and Temporal Lobe DementiaHIV-1 Associated Opportunistic Infections: Cytomegalovirus

EncephalitisMultiple SclerosisMultiple System AtrophyNeurosyphilisParkinson DiseaseParkinson-Plus SyndromesPick Disease

PrognosisAIDS dementia complex (ADC) has a variable

progression.Without treatment, the disease typically has a rapid

progression over a few months, with a mean survival rate of 3-6 months for patients with AIDS who have untreated ADC.

As a result of HAART, however, the survival rate increased from 5 months in 1993-94 to 38.5 months in the 1996-2000 period. Cognitive improvement is observed in patients with ADC after the initiation of HAART

PrognosisPoorer prognosis has been associated with the following:Lower educational levelsOlder ageLower CD4+ counts and higher HIV RNA levelsDecreased hemoglobin levelReduced platelet countThrushLow body mass indexMore constitutional symptomsHepatitis C virus co-infection

Work-upLumber puncture with CSF analysisneuroimaging studies (MRI)Electroencephalography (EEG) syphilis serology testingthyroid studieselectrolyte levelsdrug screenVitamin B-12 and folic acid levels

managementhighly active antiretroviral therapy (HAART) is the

cornerstone of treatment for HIV-related cognitive disorders (aggressive therapy)

Family counselling- psychosocial and emotional burden on family

Family education- patient have problems with compliance and adherence to their medication regimen are likely to be less inhibited . (indulge in unprotected sex)

Managementcaution is required when patients with ADC are treated

with psychoactive drugs because of enhanced susceptibility to sedative properties and possible paradoxical reactions

These drugs can up regulate the metabolism of HAART drugs, thus reducing its bioavailability.

Efavirenz should be avoided in psychiatric patients because of CNS toxicity and sucidality

ReferencesUp-to date (www.uptodate.com)Medscape

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