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Background: The clinical and laboratory characteristics of AIDS-associated Talaromyces marneffei infection, a rare but a fatal mycosis disease of the central nervous system, remain unclear., Case Presentation: Herein, we conducted a retrospective study of ten AIDS patients with cerebrospinal fluid culture-confirmed central nervous system infection caused by Talaromyces marneffei. All 10 patients were promptly treated with antifungal treatment for a prolonged duration and early antiviral therapy (ART). Among them, seven patients were farmers. Nine patients were discharged after full recovery, while one patient died during hospitalization, resulting in a mortality rate of 10%. All patients initially presented symptoms and signs of an increase in intracranial pressure, mainly manifesting as headache, dizziness, vomiting, fever, decreased muscle strength, diplopia or even altered consciousness with seizures in severe patients. Nine patients (90%) showed lateral ventricle dilatation or intracranial infectious lesions on brain CT. Cerebrospinal fluid findings included elevated intracranial pressure, increased leukocyte count, low glucose, low chloride and high cerebrospinal fluid protein. The median CD4 + T count of patients was 104 cells/μL (IQR, 36-224 cells/μL) at the onset of the disease. The CD4 + T cell counts of three patients who eventually died were significantly lower (W = 6.00, p = 0.020) than those of the patients who survived., Conclusions: The common clinical symptoms of T. marneffei central nervous system infection are associated with high intracranial pressure and intracranial infectious lesions. Earlier recognition and diagnosis and a prolonged course of amphotericin B treatment followed by itraconazole combined with early ART might reduce the mortality rate.

Mycobacterium haemophilum is an environmental organism that rarely causes infections in humans. We report a patient with acquired immunodeficiency syndrome who had central nervous system infection due to M. haemophilum. The diagnosis required brain tissue procurement and molecular identification method while the treatment outcome was unfavourable., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Neurologic disease in acquired immunodeficiency syndrome (AIDS) patients is related either to opportunistic pathogens or to direct central nervous system (CNS) invasion by the human immunodeficiency virus. Despite the increasing availability of antiretroviral therapy, opportunistic infections continue to afflict patients in the developing world and in other populations with limited access to appropriate treatment. Classic CNS infections in the setting of AIDS include toxoplasmosis, cryptococcosis, progressive multifocal leukoencephalopathy, and cytomegalovirus encephalitis. Additionally, AIDS patients are far more susceptible to acquiring CNS tuberculosis and neurosyphilis, both of which exhibit altered disease characteristics in the setting of immunosuppression. Neuroimaging is a crucial component of the diagnostic work-up of these conditions, and findings include, but are not limited to, intracranial mass lesions, white matter disease, meningoencephalitis, vascular complications, and hydrocephalus. Though various disease processes can produce imaging findings that overlap with one another, certain characteristic patterns may suggest a particular pathogen, and advanced imaging techniques and laboratory tests allow for definitive diagnosis. Knowledge of the imaging patterns seen in the setting of AIDS-related CNS disease is vital to the neuroradiologist, whose interpretation may guide decisions related to treatment and further work-up.

A marked decrease in incidence has been observed for most central nervous system (CNS) opportunistic infections (OIs) after the use of highly active antiretroviral therapy (HAART) in developed countries. However, the spectrum of these OIs in acquired immunodeficiency syndrome (AIDS) patients has remained almost unchanged. CNS toxoplasmosis, cryptococcosis, tuberculosis, and progressive multifocal leukoencephalopathy (PML) remain the most frequent ones. Primary CNS lymphoma should be included in the differential diagnosis of all cases with focal lesions. Final diagnosis is currently made by combining neuroimaging techniques (single-photon emission computed tomography [SPECT], positron emission tomography [PET], magnetic resonance imaging [MRI] and/or computed tomography [CT] scan) and molecular studies of cerebrospinal fluid (CSF) and therapeutical response. Stereotactic biopsy should only be performed in the case of atypical lesions or nonresponse to recommended treatments. After treatment of the acute phase, lifelong maintenance therapy is necessary to prevent OI recurrences. Once HAART is initiated, some patients can develop a clinical worsening of some CNS OIs with or without atypical neuroimaging manifestations. This paradoxical worsening is known as the immune reconstitution inflammatory syndrome (IRIS) and it results from reconstitution of the immune system's ability to recognize pathogens/antigens in patients with prior OIs and low CD4+ T-cell counts. In this context, IRIS can be seen in patients with CNS cryptococcosis, tuberculosis, or PML. On the other hand, HAART-induced immune reconstitution can improve the prognosis of some untreatable diseases such as PML, and can allow maintenance therapy of some CNS OI to be safely discontinued in patients with high and sustained CD4+ T-cell response.

Microglial nodules associated with opportunistic and HIV-related lesions are frequently found in the brains of AIDS patients. However, in many cases, the causative agent is only presumptively suspected. We reviewed 199 brains of AIDS patients with micronodular lesions to clarify their etiology by immunohistochemistry (to Toxoplasma gondii, cytomegalovirus, herpes simplex virus I/II, varicella zoster virus and HIV-p24 core protein), PCR (for herpetic viruses and Mycobacterium tuberculosis) and electron microscopy. Productive HIV infection was observed in 110 cases (55.1%): 30 cases with Toxoplasma gondii encephalitis, 30 with cytomegalovirus encephalitis, eight with multiple cerebral diseases, while in the remaining 42 cases HIV was the only pathogenetic agent. Multinucleated giant cells (hallmark of HIV infection) were found in the MGNs of 85/110 cases with HIV-related lesions; the remaining 25 cases had only p24 positive cells but no multinucleated giant cells. In these latter cases the micronodular lesions had been initially attributed to the main opportunistic agent found in the brain, or defined as subacute encephalitis. Individual microglial nodules positive for an opportunistic pathogen were generally negative for HIV antigens. In 13 cases no opportunistic agent or HIV productive infection was found. In these cases, PCR and electron microscopy examination for HIV and other viral infections were negative. Our data suggest that HIV-immunohistochemistry should be used for the etiological diagnosis of micronodular lesions in AIDS brains, even in the presence of other pathogens. After extensive search, the etiology of the microglial nodules remains unknown in only a small percentage of cases.

Five out of nine consecutive patients with HIV-related visceral aspergillosis observed by us since 1984 were diagnosed only at necropsy examination. The histopathological features of these five patients [two with isolated pneumonia, one with central nervous system (CNS) involvement, one with brain abscess and respiratory disease and one with pulmonary, pleural and kidney infection] have been evaluated according to epidemiological, clinical and radiological features. On the basis of our experience, life-threatening aspergillosis, which is often misdiagnosed or missed in the setting of HIV infection and AIDS, should be suspected in patients with far-advanced underlying disease and unexplained signs and symptoms, even in the absence of some presumed risk factors (i.e. neutropenia and prior steroid treatment). Plain chest radiography and bronchoscopy with broncholaveolar lavage may fail to reveal respiratory disease, CNS aspergillosis is not necessarily associated with suggestive neuroradiological features and disseminated disease may present with multiorgan failure. The unfavorable outcome of this emerging AIDS complication can be improved only by earlier diagnosis based on invasive techniques and appropriate and timely treatment.