Lymphocytopenia-associated sarcoidosis: CD4+ T-cell hypo-responsiveness to IL-2 and lectin

Cryptococcal-related meningoencephalitis in a patient with sarcoidosis and CD4 lymphocytopenia: thorough immunological characterization of lymphocyte homeostasis

Cryptococcal meningoencephalitis is the most common infective complication observed in patients with CD4 lymphocytopenia, including sarcoidosis. T-cell immunity is well characterized in HIV-related infections and data regarding immunity in cryptococcosis animal models is now available; on the contrary, little is known about the immune status in non-HIV-related infections. We report on reduced production of new T cells observed in a patient with sarcoidosis, CD4 lymphocytopenia, and cryptococcal-related meningoencephalitis. Although T cells presented with an intact proliferative capacity, they were oligoclonally expanded showing an effector memory phenotype. However, the deleterious activity of effector memory cells could have been controlled by the expansion of the regulatory T cell subset with the highest suppressive capability. This information provides a better understanding of the immune response to Cryptococcus occurring in non-HIV-associated cases, the predisposition to infection, and the role of different cell subtypes in controlling the disease in humans.

Cryptococcal meningitis complicating sarcoidosis

BACKGROUND

Cryptococcal meningitis is an uncommon but severe complication of sarcoidosis.

METHODS

We present 2 patients with cryptococcal meningitis complicating sarcoidosis and compared findings with 38 cases reported in the literature.

RESULTS

When analyzing our patients and 38 cases reported in the literature, we found that median age of sarcoidosis patients with cryptococcal meningitis was 39 years (range 30-48); 27 of 33 reported cases (82%) had a history of sarcoidosis. Only 16 of 40 patients (40%) received immunomodulating therapy at the time of diagnosis of cryptococcal meningitis. The diagnosis of cryptococcal meningitis was delayed in 17 of 40 patients (43%), mainly because of the initial suspicion of neurosarcoidosis. Cerebrospinal fluid (CSF) examination showed mildly elevated white blood cell count (range 23-129/mm). Twenty-nine of 32 cases (91%) had a positive CSF culture for Cryptococcus neoformans and 25 of 27 cases (93%) had a positive CSF C neoformans antigen test. CD4 counts were low in all patients in whom counts were performed (84-228/mL). Twelve patients had an unfavorable outcome (32%), of which 7 died (19%) and 24 patients (65%) had a favorable outcome. The rate of unfavorable outcome in patients with a delayed diagnosis was 7 of 17 (41%) compared to 5 of 28 (21%) in patients in whom diagnosis was not delayed.

CONCLUSION

Cryptococcal meningitis is a rare but life-threatening complication of sarcoidosis. Patients were often initially misdiagnosed as neurosarcoidosis, which resulted in considerable treatment delay and worse outcome. CSF cryptococcal antigen tests are advised in patients with sarcoidosis and meningitis.

Isolated Cerebellar Spindle Cell Pseudotumor Caused by Mycobacterium Avium-Intracellulare Complex in a Patient without AIDS

BACKGROUND

Spindle cell pseudotumors are formed by histiocytes in response to infection by Mycobacterium avium-intracellulare complex (MAC) and are rare in patients without AIDS.

CASE DESCRIPTION

A 66-year-old man presented with neck pain, ataxia, and a history of sarcoidosis. A cerebellar lesion was identified on magnetic resonance imaging and surgically excised. Histopathology revealed this to be a spindle cell pseudotumor and MAC was isolated by bacterial culture of cerebrospinal fluid. Hematology revealed cluster of differentiation 4 lymphocytopenia but human immunodeficiency virus serology was negative. The patient was commenced on antimicrobial treatment that included a macrolide and remained well at 1 year follow-up.

CONCLUSIONS

This rare presentation of isolated intracranial MAC was treated with surgical excision and antimicrobials with a good outcome.