Psychopharmacology 89

Which of the following is likely to lead to an opportunistic infection in a patient with AIDS?


Treponema pallidum = Syphilis

Trichomonas vaginalis = Trichomoniasis (sexually transmitted infection)

Bacillus anthracis = Anthrax

Enterobacteriaceae = Bubonic plague

HIV


The Acquired Immunodeficiency Syndrome (AIDS) is a multi-system disorder that can have psychiatric manifestations. These may be due to infection as well as from its management.

AIDS was first reported in the USA in 1981. In 1983 it was shown to be due to infection with the human immunodeficiency virus, HIV-1. This is a single-stranded retrovirus which is destructive of CD4 lymphocytes. The virus also destroys neuronal cells.

Modes of transmission:

  • sexual
  • parenteral blood or blood product recipients
  • vertical from mother to child in utero

Clinical presentation

Main clinical manifestations:

  • candidiasis
  • cryptococcus
  • cryptosporidiosis
  • cytomegalovirus
  • herpes simplex virus
  • Kaposi's sarcoma
  • mycobacterium avium
  • mycobacterium tuberculosis
  • pneumocystis jiroveci (formally known as pneumocyctis carinii)
  • toxoplasma gondii

Approximately two to four weeks after infection, the majority of patients develop a flu-like syndrome, characterised by:

  • a self-limiting fever
  • fatigue
  • rash
  • pharyngitis with cervical adenitis
  • arthralgia
  • myalgia

Following initial infection, there is usually an asymptomatic period before the onset of the various opportunistic infections

Diagnosis

Diagnosis is based on the detection of the P24 antigen, HIV nucleic acid or direct virus detection. Antibodies are detectable within about six weeks of infection and persist for life.

Severity of disease and response to treatment are monitored by measuring the CD4 count and viral load. Decreases in CD4 counts correlate with opportunistic infections. 

Most individuals are asymptomatic when their CD4 counts are >500 x 10^6/l. They are at greatest risk when this count falls below 200 x 10^6/l.

Antiretroviral drugs

These are not curative but are effective in reducing viral loads and increasing CD4 counts.

The following table illustrates the classification of antiretrovirals:

ClassExamples
Non-nucleoside reverse-transcriptase inhibitorsefavirenz
nevirapine
Nucleoside reverse-transcriptase inhibitorsabacavir
didanosine
Protease inhibitorsretinovir
indinavir
Othersenfuvirtide

Side effects from antiretrovirals are common (see table below taken from the Maudsley Guidelines):

Side effectAntiretroviral
Abnormal dreamsAtazanavir
Efavirenz
Emtricitabine
Etravirine
Lopinavir
Raltegravir
Ritonavir
Stavudine
AgitationEfavirenz
AnxietyAtazanavir
Efavirenz
Enfurvirtide
Etravirine
Lopinavir
Raltegravir
Ritonavir
Stavudine
Zidovudine
Delusions 'psychosis like behaviour'Efavirenz
DepressionAtazanavir
Efavirenz
Maraviroc
Raltegravir
Stavudine
Zidovudine
Fatal suicideEfavirenz
ManiaEfavirenz

Don't panic (too much) from seeing this table. As you can see the main one to remember is Efavirenz as it causes most problems and is most likely to appear in the exam.

Co-morbidity and prescribing

Most psychiatric conditions can co-occur.

The most prevalent psychiatric illness in people with HIV is depression (35.6%), followed by substance misuse, anxiety, psychosis, adjustment disorder and bipolar affective disorder (Knights, 2017).

The following table lists the suggestions by the Maudsley Guidelines in cases of HIV.

ProblemSuggestions
PsychosisAtypicals are suggested. Risperidone is the most widely studied
DeliriumAtypicals and low-dose short acting benzodiazepines
DepressionSSRIs, especially citalopram. Note that the following have also been specifically recommended (Knight, 2017) as first-line; selective serotonin reuptake inhibitors (SSRIs), selective noradrenaline reuptake inhibitors (SNRIs), mirtazapine and bupropion
BipolarValproate, lamotrigine, gabapentin are the best options, lithium ok but poorly tolerated. Carbamazepine is to be avoided. Atypical antipsychotics may also be used

Knights (2017) HIV infection and its psychiatric manifestations: a clinical overview. BJPsych Advances Jul 2017, 23 (4) 265-277