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Published on: September 1, 2015
Difficulty diagnosing chronic cryptococcal meningitis in idiopathic CD4+ lymphocytopenia
Giuseppe Sancesario1, Giampiero Palmieri, Gemma Viola
1Dipartimento di Neuroscienze, Università di Roma Tor Vergata, Via Montpellier 1, 00133 Rome, Italy. sancesario@med.uniroma2.it
Summary
Idiopathic CD4(+) lymphocytopenia can lead to fatal Cryptococcus neoformans infections. Macrophages efficiently engulf but poorly digest the fungus, enabling chronic intracellular infection.
Area of Science:
- Neuroimmunology
- Infectious Diseases
- Pathology
Background:
- Idiopathic CD4(+) lymphocytopenia is a rare condition characterized by a low count of CD4(+) T cells without a clear cause.
- Patients with this condition are susceptible to opportunistic infections, often presenting with unusual clinical manifestations.
Observation:
- A 64-year-old male with idiopathic CD4(+) lymphocytopenia presented with cognitive impairment, gait ataxia, and obstructive hydrocephalus.
- Autopsy revealed meningeal infiltration by CD8(+) lymphocytes and macrophages, with no CD4(+) lymphocytes.
- Cryptococcus neoformans was identified exclusively within macrophages, exhibiting intracellular budding.
Findings:
- The pathogen, Cryptococcus neoformans, was found to be localized intracellularly within macrophages in the meninges.
- Macrophages demonstrated an impaired ability to digest the phagocytized Cryptococcus neoformans, facilitating its intracellular proliferation.
- The study identified a mechanism where macrophages act as a reservoir for chronic fungal infection in the context of lymphocytopenia.
Implications:
- This case highlights a potential mechanism of opportunistic infection in idiopathic CD4(+) lymphocytopenia, where macrophage dysfunction plays a critical role.
- Understanding this pathway may inform diagnostic approaches and therapeutic strategies for cryptococcosis in immunocompromised individuals.
- The findings underscore the importance of considering fungal infections in patients with unexplained CD4(+) lymphocytopenia and neurological symptoms.
