Cryptococcosis in Adult
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Synopsis

Cryptococcosis, also known as torulosis or European blastomycosis, is a chronic fungal infection caused by Cryptococcus species. The pathogen is found worldwide in soil and avian excreta. There are 2 variants: Cryptococcus neoformans var. gattii, seen more commonly in tropical locations and in immunocompetent patients; and Cryptococcus neoformans var. neoformans, seen more commonly in immunosuppressed populations. Patients with HIV account for 80%-90% of all patients with cryptococcosis.
Primary inoculation cutaneous cryptococcosis may occur in normal and immunocompromised hosts, but infection is usually acquired by the respiratory route, with the lungs as the primary focus of the infection. In the presence of a normal immune system, the infection is usually contained and remains latent in the lung and/or hilar nodes. If there is subsequent immunosuppression, organisms may proliferate and cause symptomatic, active infection. In this situation, secondary hematogenous dissemination to the central nervous system (CNS), kidneys, and other organs including the skin occurs.
Pulmonary cryptococcosis may be heralded by chest pain and cough. In patients with HIV, it is usually more severe, especially with low CD4 counts. Headache, nausea, confusion, blurred vision, and abnormal gait may be presenting symptoms. Papilledema, cranial nerve palsies, mild fever, and mild meningismus may be present in some patients.
Cutaneous findings occur in 15%-20% of disseminated cases. The presentation is variable. Cellulitis, abscesses, papules, plaques, ulcers, sinus tracts, or purpura may all be seen. In patients with HIV, molluscum-like umbilicated papules are described.
Other possible sites of infection include the skeletal system, eyes, lymph nodes, liver, and genitourinary tract.
However, the presence of cryptococcal infection does not imply abnormal immune status; perhaps a quarter of patients have no predisposing condition. The disease has a 2:1 male predilection (even prior to AIDS).
Untreated disseminated disease is fatal. Mortality in patients with AIDS is 10%-25%.
Pediatric Patient Considerations:
Cryptococcus has been described in children without any immunodeficiency or antecedent conditions, although it most commonly occurs in children with immunodeficiencies such as HIV, status-post organ transplant, severe combined immunodeficiency syndrome, or hyperimmunoglobulin M syndrome.
Primary inoculation cutaneous cryptococcosis may occur in normal and immunocompromised hosts, but infection is usually acquired by the respiratory route, with the lungs as the primary focus of the infection. In the presence of a normal immune system, the infection is usually contained and remains latent in the lung and/or hilar nodes. If there is subsequent immunosuppression, organisms may proliferate and cause symptomatic, active infection. In this situation, secondary hematogenous dissemination to the central nervous system (CNS), kidneys, and other organs including the skin occurs.
Pulmonary cryptococcosis may be heralded by chest pain and cough. In patients with HIV, it is usually more severe, especially with low CD4 counts. Headache, nausea, confusion, blurred vision, and abnormal gait may be presenting symptoms. Papilledema, cranial nerve palsies, mild fever, and mild meningismus may be present in some patients.
Cutaneous findings occur in 15%-20% of disseminated cases. The presentation is variable. Cellulitis, abscesses, papules, plaques, ulcers, sinus tracts, or purpura may all be seen. In patients with HIV, molluscum-like umbilicated papules are described.
Other possible sites of infection include the skeletal system, eyes, lymph nodes, liver, and genitourinary tract.
However, the presence of cryptococcal infection does not imply abnormal immune status; perhaps a quarter of patients have no predisposing condition. The disease has a 2:1 male predilection (even prior to AIDS).
Untreated disseminated disease is fatal. Mortality in patients with AIDS is 10%-25%.
Pediatric Patient Considerations:
Cryptococcus has been described in children without any immunodeficiency or antecedent conditions, although it most commonly occurs in children with immunodeficiencies such as HIV, status-post organ transplant, severe combined immunodeficiency syndrome, or hyperimmunoglobulin M syndrome.
Codes
ICD10CM:
B45.9 – Cryptococcosis, unspecified
SNOMEDCT:
42386007 – Cryptococcosis
B45.9 – Cryptococcosis, unspecified
SNOMEDCT:
42386007 – Cryptococcosis
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Diagnostic Pearls
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Differential Diagnosis & Pitfalls
- Molluscum contagiosum
- Molluscum-like papules (ie, Penicillium marneffei infection, histoplasmosis, coccidioidomycosis)
- Cutaneous leishmaniasis
- Erythema nodosum
- Syphilis
- Histoplasmosis
- Cutaneous tuberculosis
- Sarcoidosis
- Bacterial cellulitis
- Cryptococcoid Sweet syndrome
- Pneumocystis jirovecii pneumonia
- Mycobacterium tuberculosis infection
- Mycobacterium avium-intracellulare infection
- Cytomegalovirus infection
- Histoplasma capsulatum infection
- Coccidioidomycosis
- Nocardiosis
- Legionellosis
- Viral infection (eg, adenovirus)
- Septic emboli – especially in patients who have indwelling central venous catheters
- Malignancy (including lymphoma)
Best Tests
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Therapy
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Drug Reaction Data
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.
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References
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Last Reviewed:03/19/2017
Last Updated:08/07/2023
Last Updated:08/07/2023
Cryptococcosis in Adult
See also in: Cellulitis DDx