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Published on: September 5, 2017
[Cryptococcus neoformans meningitis in a HIV negative miliary tuberculosis-suspected patient]
Hande Aydemir1, Nihal Pişkin, Nefise Oztoprak
1Zonguldak Karaelmas Universitesi Tip Fakültesi, Enfeksiyon Hastaliklari ve Klinik Mikrobiyoloji Anabilim Dali, Zonguldak. drhaydemir@yahoo.com
Abstract:
Cryptococcosis caused by Cryptococcus neoformans has a wide range of clinical presentations, varying from asymptomatic colonization of the respiratory airways to the dissemination of infection into different parts of body. It is more common among immunosupressed patients such as human immunodeficiency virus (HIV) positive ones. In this report we present a case with C. neoformans meningitis and miliary pulmonary infiltrates suggesting pulmonary tuberculosis without HIV infection. A-70-years-old male was admitted to the hospital with mental confusion, 3-weeks history of headache, weight loss, dry cough and fatigue. Physical examination was normal except neck stiffness. Cerebrospinal fluid (CSF) white cell count was 120/mm3 (80% polimorphonuclear cells). Gram staining of CSF revealed poorly stained gram-positive yeast cells. Empirical therapy with lipozomal amphotericin B, ceftriaxone and ampicillin combination was started. When C. neoformans growth was detected on CSF culture, ceftriaxone and ampicillin were discontinued. Patient became conscious at 24th hour of the treatment. Peripheric blood flow-cytometric analysis revealed a significant decrease in absolute CD4+ T lymphocytes, and in CD8+28+ T lymphocytes in addition a significant increase in natural killer cell ratio. Blood immunoglobulin and complement levels were found normal. Cranial magnetic resonance imaging and computerized tomogralphy (CT) of the abdomen were normal, however, chest CT revealed multiple parenchymal millimetric nodular infiltrations on both sides and minimal fibrotic alterations. Acid-fast staining of CSF, tuberculosis culture, tuberculosis PCR results and repeated HIV serology were found negative. Despite the lack of microbiological confirmation, empirical antituberculosis treatment was also started with the suspicion of miliary tuberculosis as the patient had a symptom of long-term dry cough, miliary infiltrations on chest CT, anergic tuberculin skin test and a history of pulmonary tuberculosis in childhood. After two weeks, amphotericin B was changed to oral fluconazole which was continued for an additional eight weeks. Antituberculosis therapy was given for nine months. Control chest CT taken after four months of antituberculosis therapy revealed improvement of the lesions. This presentation emphasizes the fact that cryptococcal infections may develop in HIV negative patients, even together with tuberculosis in certain cases and radiological findings of the two infections may be confusing when both of them invade the lungs.
Insights
This case report highlights cryptococcosis in an HIV-negative patient, presenting with meningitis and pulmonary infiltrates mimicking tuberculosis. It underscores that cryptococcal infections can occur in non-immunocompromised individuals and co-exist with tuberculosis.
Area of Science:
- Infectious Diseases
- Mycology
- Immunology
Background:
- Cryptococcosis, caused by Cryptococcus neoformans, typically affects immunocompromised individuals, often presenting as meningitis or disseminated disease.
- Coinfection with tuberculosis can complicate diagnosis, particularly in HIV-negative patients, due to overlapping clinical and radiological features.
Observation:
- A 70-year-old male presented with cryptococcal meningitis and miliary pulmonary infiltrates, initially suspected as tuberculosis, despite being HIV-negative.
- Cerebrospinal fluid analysis revealed yeast cells, and blood tests indicated altered T-lymphocyte subsets and increased natural killer cells.
- Chest CT showed diffuse nodular infiltrates suggestive of miliary tuberculosis, though microbiological tests for tuberculosis were negative.
Findings:
- Successful treatment of cryptococcal meningitis with liposomal amphotericin B followed by fluconazole.
- Empirical antituberculosis therapy was administered for nine months due to suspected miliary tuberculosis, leading to improvement in pulmonary lesions.
- The patient's immune status showed a decrease in CD4+ and CD8+ T lymphocytes and an increase in NK cells, without a definitive diagnosis of immunodeficiency.
Implications:
- Cryptococcal infections should be considered in HIV-negative individuals presenting with meningitis and pulmonary infiltrates, even when tuberculosis is suspected.
- Radiological findings in pulmonary cryptococcosis and tuberculosis can be similar, necessitating a high index of suspicion and comprehensive diagnostic workup.
- This case emphasizes the importance of considering non-HIV-related immunosuppression or immune dysregulation in the pathogenesis of opportunistic infections like cryptococcosis.
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