Successful Treatment of DisseminatedAcanthamoebasp. Infection with Miltefosine

Abstract

We report on an HIV-negative but immunocompromised patient with disseminated acanthamoebiasis, granulomatous, amoebic encephalitis, and underlying miliary tuberculosis and tuberculous meningitis. The patient responded favorably to treatment with miltefosine, an alkylphosphocholine. The patient remained well with no signs of infection 2 years after treatment cessation.A 25-year-old man from India, who had been living in Austria for 7 years and had no previous history of major illnesses, was brought by ambulance to the hospital for dyspnea, cough, fever, and weight loss. During neurologic examination, a hearing impairment was suspected. The patient was unable to walk because of severe ataxia. Skin examination showed several necrotic ulcers with purulent discharge and black eschars, measuring 0.5 cm to 3 cm, located on the skull, back, neck, and arms ( Figure 1, panels A and B). Miliary tuberculosis (TB) of the lungs, liver, spleen, and kidneys was suspected on the basis of chest radiography and computed tomography (CT) of chest and abdomen. Ziehl-Nielsen (ZN) staining for acid-fast bacilli in sputum, bronchial secretions, and lavage obtained through bronchoscopy was negative. PCR for Mycobacterium tuberculosis in bronchial secretions and serum was positive. Culture on Loewenstein agar resulted in growth of nonresistant M. tuberculosis after 31 days. Blood cultures were negative for aerobic/anaerobic bacteria, mycobacteria, and fungi. Results of serologic tests were negative for Aspergillus, Candida, Cryptococcus, Histoplasma, Blastomyces, and Coccidioides spp. Severe immunosuppression with a CD4+ lymphocyte count of 182 cells/μL made HIV infection probable, but HIV testing results were negative. Cranial CT showed multiple small enhancing lesions in cerebral cortex and underlying white matter, pons, midbrain, and around most of the cisterns. On magnetic resonance imaging (MRI), the lesions appeared as high T2 signal areas that enhanced heterogeneously or in a ringlike manner. These fi ndings were compatible with the diagnosis of meningoencephalitis with intracerebellar abscess formation.Cerebrospinal fl uid (CSF) obtained through lumbar puncture was negative for Toxoplasma gondii, Encephalitozoon cuniculi, and Enterocytozoon bieneusi by PCR and for Trypanosoma gambiense by indirect hemagglutination assay. Staining and antigen testing (enzyme immunoassay) for Cryptococcus neoformans was negative, as was Treponema pallidum antibody testing. No viruses (herpes simplex 1 and 2, varicella zoster, enterovirus) could be detected by PCR. Cultures were negative for aerobic/ anaerobic bacteria and fungi. ZN staining detected acid-fast bacilli that were confi rmed to be nonresistant M. tuberculosis after culture for 38 days. PCR for M. tuberculosis was positive. An Acanthamoeba-specifi c PCR (1) and DNA sequencing of the PCR product showed Acanthamoeba genotype T2 (corresponding to group III). High immunoglobulin (Ig) G (2,000) and IgM (1,000) titers against Acanthamoeba spp. could be demonstrated serologically. The organism ...

Balamuthia mandrillaris and Acanthamoeba Amebic Encephalitis with Neurotoxoplasmosis Coinfection in a Patient with Advanced HIV Infection

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