5-step psychiatric workup of HIV patients

• HIV and syphilis share sexual risk factors
  
• having syphilis increases the likelihood of comorbid HIV infection 7- to 9-fold¹¹
  
• syphilis may worsen the course of HIV infection¹²
  
• syphilis can mimic psychiatric symptoms.^13,14
  

STEP 3 Order neuroimaging

Neuroimaging is an essential part of the workup of a patient for whom your clinical examination raises suspicion for CNS impairment. In patients with longstanding HIV infection, brain imaging may reveal cerebral atrophy, which may accompany the cognitive changes found in HIV-associated dementia. In addition, immunocompromised patients, particularly those with a CD4 count 15

CASE CONTINUED

Brain MRI shows moderate cerebral and cerebellar atrophy, which ID clinicians attribute to the long-term effects of HIV infection. No evidence of focal or mass lesions is seen.

By further investigating Mr. G’s medical records, you find a brain MRI performed when Mr. G initially presented with toxoplasmosis in 2001. This scan reveals a large ring-enhancing mass in the right frontal lobe. Although the patient had refused a brain biopsy, the radiologist determined the lesion was most consistent in appearance with intracranial toxoplasmosis.

STEP 4 Perform neuropsychological testing

When physical exam, mental status exam, or neuroimaging suggests a possible CNS cause for a patient’s psychiatric presentation, neuropsychological testing can help characterize which of the patient’s brain functions are compromised and determine their anatomic source. This testing allows for a more complete and precise assessment of brain function than can be achieved by a bedside cognitive exam. It typically includes the Trail Making Test Parts A and B and the Grooved Pegboard Test to evaluate executive and psychomotor functioning, as well as the Controlled Oral Word Association Test to evaluate cognitive speed.

CASE CONTINUED

A search of medical records reveals that Mr. G had recently undergone a brief neuropsychological assessment at the hospital’s outpatient HIV mental health clinic. The psychologist found evidence of frontal lobe dysfunction, including problems with shifting sets, verbal fluency, and naming the months of the year backwards. Mr. G’s performance demonstrated a subcortical dementia pattern that included prominent fine motor impairment.

STEP 5 Synthesize all data to make a diagnosis

Psychiatric illness in HIV-positive patients may involve factors at multiple biopsychosocial levels, including problems with social support, psychological stress, primary psychiatric illness, immunocompromise, and CNS disease. Consider data from all of these levels to arrive at a diagnosis.

CASE CONTINUED

After carefully considering Mr. G’s history, physical and mental status examinations, laboratory data, current and past neuroimaging, and neuropsychological testing, you and ID clinicians conclude that Mr. G’s neuropsychiatric presentation primarily represents the residual deficits from his large frontal lobe toxoplasmosis lesion diagnosed in 2001, with possible contribution from an underlying HIV-associated dementia. You feel that a depressive disorder can be ruled out with a high degree of certainty because the patient denied abnormalities of mood or hedonic tone, did not demonstrate deficits in neurovegetative functioning such as appetite, energy, and sleep, and did not show evidence of suicidality. You attribute the flat affect and amotivation that had prompted the psychiatric consult to his secondary neuropsychiatric deficits.

Table 3

Staging system for HIV-associated dementia