Involvement of the nervous system in HIV infection is common, manifesting in about half of patients.
Aseptic meningitis. At the time of HIV seroconversion or primary infection, patients may present with symptoms of aseptic meningitis, such as fever, headache, stiff neck, and a lymphocytic pleocytosis.
AIDS dementia complex
AIDS dementia complex is reported in about 6% to 7% of patients with AIDS. Clinical features include cognitive dysfunction, impaired motor performance, and behavioral changes. Subclinical cognitive and motor impairment may occur at all stages of HIV infection.
Progressive symptoms may include mental slowing, forgetfulness, poor concentration, apathy, social withdrawal, loss of spontaneity, and reduced libido. Patients display personality changes, including reduced emotional expression, increased irritability, mania, and disinhibition. Loss of fine motor control (deterioration in handwriting), slowing of gait, unsteadiness, urinary incontinence, and may be seen. Seizures occur in 10% of patients.
AIDS dementia complex is a diagnosis of exclusion because depression, metabolic disorders, and other infectious causes of encephalitis may present in a similar manner. Clinical diagnosis may be aided by neuropsychologic testing.
Central nervous system (CNS) computed tomography (CT) and magnetic resonance imaging (MRI) are used to exclude other treatable conditions. They may reveal cerebral atrophy.
AIDS dementia complex may respond to highly active antiretroviral therapy, which should include of at least one agent that has significant CNS penetration. Discount Canada Drugs Online
HIV-related spinal cord involvement is uncommon. It presents as spastic paraparesis with bowel and bladder dysfunction, gait ataxia, and variable sensory loss, usually in the context of advanced immunodeficiency.
Diagnosis must exclude cord-compression lesions (eg, lymphoma, epidural abscess), and other viral infections (eg, human T-cell lymphotropic virus type I, varicella-zoster virus, cytomegalovirus).
Myelopathy may respond to highly active antiretroviral therapy. Additional treatment should be directed at ameliorating symptoms.
Distal symmetric polyneuropathy
Distal sensory polyneuropathy may develop as a consequence of HIV infection, but it is more commonly associated with use of antiretroviral agents, specifically zalcitabine (HIVID), didanosine (Videx), and stavudine (Zerit). It tends to occur with advanced infection. Symptoms typically consists of distal paresthesias, with burning sensations and numbness of fingertips and toes, that progress proximally. Canada drug store
Physical examination reveals diminished ankle reflexes and decreased sensation to pinprick, light touch, and vibration. Nerve-conduction tests demonstrating axonal neuropathy can confirm the diagnosis. The possibility of deficiency should be excluded.
Management consists of dose reduction or discontinuation of any potentially offending agents. Symptomatic treatment with tricyclic antidepressants, anticonvulsants (eg, carbamazepine, gabapentin [Neurontin]), lidocaine 30% cream, and narcotic analgesics may be effective.
Cerebral toxoplasmosis occurs as a consequence of reactivation, developing in about 2% to 10% of patients with HIV infection and prior toxoplasma infection (identified by positive IgG titers). Most cases occur when the CD4+ T-lymphocyte count is less than 100 cells/FL.
Clinical manifestations include headache, confusion, fever, focal neurologic deficits, and seizures. CT and MRI reveal lesions with ring enhancement. Lesions are often multiple with associated mass effect involving the frontal and parietal lobes and basal ganglia. Characteristic CT or MRI findings and positive serologic results are indications for empirical therapy. Definitive diagnosis is by brain biopsy.
Treatment regimens consisting of sulfadiazine or of clindamycin (Cleocin) plus pyrimethamine (Daraprim) for 6 weeks have been equally effective. Clinical improvement is usually seen in 10 to 14 days. Lifetime suppressive therapy is recommended.
Patients at risk for toxoplasmosis (CD4+ count less than 100 cells/FL and positive serology) should be offered primary prophylaxis with trimethoprim-sulfamethoxazole (Bactrim, Septra) or dapsone plus pyrimethamine. Canada rx drug
Cryptococcus neoformans can cause fungal meningitis in the presence of HIV infection, usually in patients with a CD4+ count less than 100 cells/FL. The organism disseminates widely, with predilection for the CNS.
Headache and fever are the most common presenting symptoms; others include nausea and vomiting, photophobia, blurred vision, stiff neck, skin lesions, altered mentation, and seizures.
CSF culture confirms the diagnosis. India ink preparations of CSF and cryptococcal antigen testing of serum and CSF are usually positive. Blood cultures are positive in only about one fourth of cases. Neuroimaging may reveal cryptococcomas, hydrocephalus, and cerebral edema. The mortality rate of cryptococcal meningitis is 10% to 20%. Canadian drug pharmacy
Antifungal treatment regimens include either amphotericin B ( Fungizone) and flucytosine ( Ancobon) or amphotericin B alone for 2 weeks, followed by daily fluconazole ( Diflucan).
Elevated intracranial pressure should be aggressively managed with CSF drainage by lumbar puncture, ventriculoperitoneal shunting, and acetazolamide (Diamox). Long-term suppression with fluconazole is recommended to avoid recurrence.
Progressive multifocal leukoencephalopathy
Reactivation of latent JC virus results in progressive multifocal leukoencephalopathy. This condition usually occurs when CD4+ counts are less than 100 cells/FL. Clinical features are subacute in onset and include limb weakness, impairment of cognitive function, gait disturbance, incoordination, speech and visual disturbances, headache, and seizures.
CT typically shows hypodense white-matter lesions, usually parietooccipital, with no enhancement or mass effect. MRI may more clearly show lesions.
A positive CSF polymerase chain reaction for JC virus is diagnostic; however, a negative result cannot exclude the diagnosis. The prognosis of progressive multifocal leukoencephalopathy is poor. Remission with potent antiretroviral therapy may occur. Drug world pharmacy
In patients with a CD4+ T-lymphocyte count less than 100 cells/FL, CMV disease develops within 2 years in 21.4%. The usual presentation consists of retinitis and esophagitis, with or without colitis; pneumonitis, hepatitis, encephalitis, and polyradiculopathy also may occur.
Clinical features of encephalitis include rapidly progressive confusion, delirium, apathy, and focal neurologic deficits. CT may reveal diffuse low-attenuation areas. MRI reveals high signal intensity lesions on T2-weighted images. Periventricular enhancement and edema are characteristic. CSF yields nonspecific findings.
Polyradiculopathy manifests as lower extremity weakness, paresthesias, and bladder and bowel dysfunction. Saddle pain and urinary retention are common. Elevated protein level and polymorphonuclear pleocytosis are noted on CSF analysis. Detection of CMV DNA on CSF polymerase chain reaction testing is diagnostic. Canadian pharmacy store online
Ganciclovir sodium (Cytovene) and foscarnet (Foscavir) have had variable effectiveness in treatment of CMV infection of the CNS.
In patients with HIV infection, neurosyphilis develops within a shorter interval. The prevalence of syphilitic meningitis, uveitis, and hearing loss is increased.
Asymptomatic patients with positive serologic findings should undergo CSF examination for exclusion of neurosyphilis.
Lymphoma in the CNS occurs in 5% of patients with AIDS, usually late in the disease course. Manifestations may include headaches, mental status changes, seizures, and focal neurologic signs and symptoms.
Lesions most commonly affect the periventricular gray and white matter; most are supratentorial, but some are multifocal. CT and MRI reveal single or multiple discrete mass lesions with diffuse homogeneous contrast enhancement and some mass effect. drug pharmacy quality
Thallium 201 single-photon emission CT of the brain can help distinguish lymphoma from toxoplasmosis, but brain biopsy is required for diagnosis.
Prognosis of CNS lymphoma is poor. Response of lesions to radiation therapy is variable.