Histoplasmosis-Epidemiology

Iriabel Nepravishta

The disease is caused by Histoplasma capsulatum.
The disease is widely spread in Latin America, Puerto Rico, and in Midwest U.S.
It’s pandemic among HIV-infected persons in endemic regions.
In non pandemic regions, it’s seen in people who were earlier inhabitants of endemic regions (Staffolani et al., 2018).
Acquired by breathing infected air.
It should be mentioned that risks of getting the diseases include: disturbing birds, exploring caves, working with contaminated soil, and living in areas inhabited with bat.

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Histoplasmosis-Signs & Symptoms

People with infected disease exhibits:
Fever

Weight loss

Fatigue

Majority experience chest pain and cough

Headache and altered mental status is a common manifestation.
Study shows that isolated pulmonary disease is common in patients with more than 300 CD4 count.
Patients also diarrhea and experience abdominal pain.
Disseminated disease is common in patients with low CD4 counts.

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Histoplasmosis-Alteration of Tissues.

Chest

X-ray & CT Scan

Images courtesy of AIDS image Library (www.aids-images.ch)

Histoplasmosis-Clinical Manifestation (2)

Images courtesy of AIDS image Library (www.aids-images.ch)

Skin lesions of histoplasmosis

Pathophysiological Alterations.

Diagnosis.

Histoplasma antigen detected in:
Serum

Urine

Culture from: Blood, bone marrow and in some cases respiratory secretions.

Serologic tests are appropriate to patient with higher CD4 count.

Serologic tests are not advised for patients with disseminated disease or in AIDS.

Antigen tests provides up to 70% accuracy.

Presumptive diagnosis is considered for patients with disseminated disease as well as those with CNS infection.

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Intervention.

The first prevention should be to avoid exposure.
In pandemic regions, it may be impossible to avoid exposure entirely.

People with less CD4 count should avoid higher-risk activities.

Itraconazole reduce frequency of diseases in patients with HIV infection.
Though Intraconazole significantly reduce frequency of disease in HIV infected patients, there is no survival benefit.
Conferring with Chroboczek et al (2018) discontinuing prophylaxis is a prevention intervention.
Less CD4 counts-150 cells/µL
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Pharmacological-Interventions.

Less severe disease.
Induction

Maintenance

Medication-Intraconazole 200 mg PO TID for 3 days.
Alternative. (There is limited data)
Posaconazole 400 mg PO BID

Voriconazole 400 mg PO BID –one day then half the dosage.

Fluconazole 800 mg PO BID.

Histoplasmosis-Monitoring.

Monitor urine or serum.
This helps to evaluate response to therapy.
As revealed by Zanotti et al (2018) increase in level suggests relapse.
Regularly check itraconazole levels-This should be after 2 weeks of therapy.
Incase of treatment failure, posaconazole should be considered for moderately ill patients.
Liposomal amphotericin B should be used for severely ill patients.
References.

Staffolani, S., Buonfrate, D., Angheben, A., Gobbi, F., Giorli, G., Guerriero, M., … & Barchiesi, F. (2018). Acute histoplasmosis in immunocompetent travelers: a systematic review of literature. BMC infectious diseases, 18(1), 673.
Chroboczek, T., Dufour, J., Renaux, A., Aznar, C., Demar, M., Couppie, P., & Adenis, A. (2018). Histoplasmosis: An oral malignancy-like clinical picture. Medical mycology case reports, 19, 45-48.