• New York State Department of Health. Infectious complications associated with HIV infection: parasitic infections. New York (NY): New York State Department of Health; 2006 Nov. 20 p. [47 references]

This is the current release of the guideline.

The quality of evidence (I-III) is defined at the end of the "Major Recommendations" field.

Pneumocystis jirovecii (PCP)

Presentation

Clinicians should place all hospitalized human immunodeficiency virus (HIV)-infected patients with respiratory symptoms and/or abnormal chest x-rays in respiratory isolation in a negative pressure room until active pulmonary tuberculosis is excluded or an alternative diagnosis that accounts for the abnormalities is established. (I)

Diagnosis

Clinicians should obtain evidence of the characteristic organisms in induced sputum, bronchoalveolar lavage fluid, or tissue specimen. (III)

Clinicians should obtain a bronchoalveolar lavage if induced sputum is negative or unavailable. (III)

Treatment

Clinicians should treat PCP with trimethoprim/sulfamethoxazole (TMP/SMX) administered either parenterally or orally, depending on the severity of the illness and likelihood of adherence. A total of 21 days of therapy should be completed. Dosing regimens and alternative drugs are listed in the table below. (I)

Clinicians should hospitalize patients with severe disease, as defined by initial room air pO₂ of <70 mm Hg or an arterial-alveolar oxygen gradient of >35 mm Hg, and administer parenteral treatment with the most effective agent and steroids. (I)

If PCP fails to improve within 7 to 10 days of treatment, clinicians should consider an alternative diagnosis and a change in PCP therapy, generally from trimethoprim/sulfamethoxazole to intravenously administered pentamidine. (II)

Clinicians should administer adjunctive steroids to persons with PCP who have significant hypoxia (see table below). (I)

Clinicians should initiate secondary prophylaxis to prevent recurrence of PCP immediately after completion of the treatment regimen. (II)

Table
Treatment of PCP in HIV-Infected Individuals

* The dose of 15 mg /kg is as effective as the dose of 20 mg/kg and has less hematological toxicity.
** The efficacy of clindamycin has not been established for the treatment of severe disease.
*** Check glucose-6 phosphate dehydrogenase (G6PD) screen prior to initiation. Hemolytic anemia may occur in some cases of G6PD deficiency.

Prevention

Clinicians should initiate PCP prophylaxis in patients with CD4 cell counts <200 cells/mm³, or ≤14% of total lymphocytes, and in patients with higher CD4 counts who have a history of PCP, thrush, or unexplained constitutional symptoms of >2 weeks' duration (I). TMP/SMX is the referred prophylactic agent for PCP (I). See the table below for specific recommendations.

Clinicians should discontinue primary and secondary PCP prophylaxis when patients have responded to highly active antiretroviral therapy (HAART) with a sustained CD4 cell count of ≥200 cells/mm³ for ≥3 months. (I)

Table
Prophylactic Regimens for PCP

DS, double strength; SS, single strength.
* There is an increased risk of prophylaxis failure with advancing immunosuppression, especially for non-TMP/SMX regimens.
** 1 DS tablet TMP/SMX is effective for prophylaxis against toxoplasmosis as well. Lower doses might also provide such protection.
*** Exclude G6PD deficiency before initiating. Hemolytic anemia may occur in some cases of G6PD deficiency.
# This regimen is effective prophylaxis against toxoplasmosis in individuals who are intolerant to TMP/SMX.
¶ Results from CPCRA/ACTG 277 showed that atovaquone in suspension, at the dose of 1500 mg PO daily is comparable to dapsone for PCP prophylaxis. No overall differences in the rate of adverse effects were noted in this study. Although some patients may better tolerate dapsone, the relative risk for discontinuation was greater with this agent than with atovaquone. Atovaquone is significantly more expensive.

Toxoplasma gondii

Diagnosis

Although the definitive diagnosis of toxoplasma encephalitis requires a brain biopsy, clinicians should use the following presumptive criteria to diagnose cerebral toxoplasmosis (II):

• Multiple ring-enhancing central nervous system mass lesions demonstrated by an imaging study; magnetic resonance imaging (MRI) is more sensitive than a contrast-enhanced computed tomography (CT) scan
• Positive serum immunoglobulin G (IgG) to T. gondii
• CD4 count <100 cells/mm³
• Lack of toxoplasmosis prophylaxis

Clinicians should consider alternative diagnoses if there is an absence of serum IgG antibodies to T. gondii. (III)

Clinicians should obtain a brain biopsy to establish a definitive diagnosis if the patient fails to clinically and radiographically respond to therapy within 10 to 14 days or the presentation is unusual enough to make the diagnosis uncertain. (III)

Treatment

Clinicians should continue acute therapy for toxoplasmosis until there is clinical improvement and radiographic evidence of reduction in size and number of lesions (for 4 to 6 weeks) and should follow with suppressive therapy. (III)

Table
Treatment of Acute Toxoplasmosis in HIV-Infected Patients

Table
Prevention of Recurrent Toxoplasmosis in HIV-Infected Patients

Prevention

Clinicians should initiate prophylaxis for toxoplasmosis when a patient's CD4 count decreases to <100 cells/mm³ and the patient is toxoplasma IgG positive (I). TMP/SMX is the preferred prophylactic agent for toxoplasmosis (I). (Refer to table below).

Clinicians should discontinue primary toxoplasmosis prophylaxis when patients have responded to HAART with a sustained (≥3 months) increase in CD4 cell count (>200 cells/mm³). (I)

Clinicians should counsel HIV-infected toxoplasma-seronegative patients to avoid undercooked meats and to carefully wash hands after handling cat litter boxes and after gardening. (III)

Table
Toxoplasmosis Prophylaxis Regimens in HIV-Infected Patients

DS, double strength; SS, single strength.
* Exclude G6PD deficiency before initiating.

Cryptosporidiosis

Presentation

Clinicians should include cryptosporidiosis in the differential diagnosis of diarrhea, especially large-volume diarrhea. (I)

Diagnosis

Clinicians should specifically request acid-fast staining or immunofluorescent antibody testing of the stool to establish a diagnosis of cryptosporidiosis. (I)

Clinicians should specifically alert the laboratory to look for cryptosporidia if this diagnosis is suspected (III).

Treatment

Clinicians should prescribe a combination of paromomycin 1 g twice a day (bid) plus azithromycin 600 mg orally (PO) daily for 4 weeks, followed by paromomycin maintenance therapy. (III)

Prevention

Clinicians should counsel patients to:

• Avoid contact with human and animal feces, pets with diarrhea, dogs or cats <6 months of age
• Avoid drinking water from lakes, streams, or rivers, unless it has been adequately boiled
• Boil water for 1 minute when public health agencies issue a boil-water advisory during waterborne outbreaks of cryptosporidiosis

Isospora belli

Diagnosis

Because Isospora belli is shed intermittently in the stool, clinicians should request multiple stool specimens for modified acid-fast stool staining. (I)

Treatment

Clinicians should treat Isospora belli with TMP/SMX double strength (DS) PO four times daily for at least 10 days. (I)

Clinicians should consider using pyrimethamine 50 to 75 mg/day for 10 days in patients allergic to sulfa, followed by leucovorin 5 to 10 mg/day. (III)

Clinicians should consider discontinuing isosporiasis prophylaxis for patients who are asymptomatic and have sustained CD4 >200 cells/mm³ for ≥3 months. (III)

Cyclospora

Diagnosis

Clinicians should base the diagnosis of cyclosporiasis on microscopic detection of oocysts in stool. (I)

Treatment

Clinicians should prescribe oral TMP/SMX 160 mg/800 mg four times a day for 10 days, followed by secondary prophylaxis with TMP/SMX three times a week to treat Cyclospora infection in HIV-infected patients. (I)

Giardia

Treatment

Clinicians should treat Giardia with metronidazole 250 mg PO three times a day (tid) for 5 to 10 days. (I)

Clinicians should educate Giardia-infected patients regarding improved hygienic measures. (III)

Amebiasis

Diagnosis

Clinicians should obtain at least three stool specimens before excluding the diagnosis of amebiasis. (II)

Treatment

Clinicians should initiate treatment of Entamoeba histolytica when trophozoites with ingested red blood cells are present in the stool. One of the following regimens should be used (II):

• Metronidazole 750 mg tid for 10 days or 2.4 g daily (qd) for 3 days
• Tinidazole 2 g PO qd for 3 days followed by paromomycin 500 mg tid for 7 days
• Iodoquinol 650 mg tid for 20 days

Clinicians should treat patients with asymptomatic E. histolytica infection with one of the following regimens (II):

• Paromomycin 500 mg tid for 7 days
• Iodoquinol 650 mg tid for 20 days
• Diloxanide furoate 500 mg tid for 10 days

Clinicians should treat extraintestinal disease with metronidazole 750 mg tid for 10 days or 2.4 g qd for 3 days (II).

Definitions:

Quality of Evidence for Recommendation

1. Evidence from one or more properly randomized, controlled trial
2. Evidence from one or more well-designed clinical trial without randomization; from cohort or case-controlled studies
3. Evidence from opinions of respected authorities based on clinical experience, descriptive studies, or reports of expert committees

None provided

The type of supporting evidence is classified for selected recommendations (see "Major Recommendations").

• New York State Department of Health. Infectious complications associated with HIV infection: parasitic infections. New York (NY): New York State Department of Health; 2006 Nov. 20 p. [47 references]

Not applicable: The guideline was not adapted from another source.

2006 Nov

New York State Department of Health - State/Local Government Agency [U.S.]

New York State Department of Health

Not stated

Not stated

Not stated

This is the current release of the guideline.

None available

This NGC summary was completed by ECRI Institute on September 7, 2007.