Systemic acanthamoebiasis associated with canine distemper in dogs in the semiarid region of Paraíba, Brazil

Infections by free-living amoebae can cause systemic disease in animals and humans. We describe the epidemiological, clinical and pathological aspects of disseminated acanthamoebiasis associated with canine distemper in three dogs of the semiarid region of Paraíba, Northeastern Brazil. Affected dogs developed progressive neurological and respiratory signs that progressed to death within in two to 20 days. Gross lesions were irregular and with yellow-reddish nodules randomly distributed in the lungs, heart, kidneys, spleen, lymph nodes, adrenals, and intestine. One dog had foci of malacia in the parietal cortex and another one in nucleus of brain basis. Histologically, pyogranulomas with areas of necrosis and hemorrhage in all organs affected were observed, associated with myriads of intralesional amoebic trophozoites. All three cases were concomitant canine distemper, that possibly triggered immunosuppression in the dogs. The diagnosis was performed through microscopic findings of infection by free-living amoebae and confirmed Acanthamoeba sp. by immunohistochemistry.

Infecções por amebas de vida livre podem causar doença sistêmica nos animais e no homem. Descrevem-se os aspectos epidemiológicos, clínicos e patológicos de acanthamoebíase disseminada associada com cinomose em três cães na região semiárida da Paraíba, Nordeste do Brasil. Os cães afetados desenvolveram sinais respiratórios e neurológicos progressivos, que evoluíram para a morte em dois a 20 dias. Na necropsia havia áreas nodulares, irregulares e amarelo-avermelhadas distribuídas aleatoriamente em pulmões, coração, rins, fígado, baço, linfonodos, adrenal e intestino. Em um caso havia foco de malácia no córtex parietal e outro em núcleo da base encefálica. Histologicamente, foram observados piogranulomas com áreas de necrose e hemorragia em todos os órgãos afetados, associados a miríades de amebas intralesionais. Nos três casos havia cinomose concomitante, que possivelmente desencadeou imunossupressão nos cães. O diagnóstico foi realizado através dos achados microscópicos de infecção por amebas de vida livre e confirmado Acanthamoeba sp. pela imuno-histoquímica.

Acanthamoebiasis in Korea: two new cases with clinical cases review

The first case was 7-month-old immunodeficiency girl in whom the diagnosis of Acanthamoeba pneumonia was established by culture of a bronchial washing. The patient had been ill for a month when she was admitted due to neonatal thrombocytopenia with respiratory difficulty and treated with gammaglobulin and steroid. Her chest X-ray showed diffuse alveolar consolidation on the left lung with interstitial hazziness and a partial sign of hyperinflation on the right lung. Laboratory tests showed that the Candida antigen was negative and Pneumocystis carinii was not detected. Mycoplasma antigen was negative. All the immunoglobulin levels (IgG, IgA, IgM) were below the normal range. Five days later the patient expired. The second case was an immunosuppressed 7-year-old boy in whom Acanthamoeba trophozoites were found in the skin biopsy, followed by meningitis leading to death. About five days after a laceration on the region of the left eyebrow, a painful bean-sized nodule developed at the suture site and it was treated with antibiotics and corticosteroid. The skin biopsy showed severe inflammatory cell infiltration. Trophozoites were scattered near the blood vessels throughout the inflammatory zone. From one weak prior to admission, the patient had suffered from vomiting, indigestion and mild fever. Skin nodules with tenderness appeared all over his body surface. Examination of cerebrospinal fluid showed clear, Gram stain was negative, bacterial culture negative, India ink preparation negative, and organism on wet smear negaive. On admission day 10, focal seizure of the left extremity occurred. Brain CT revealed calcific density on the left parietal lobe area and hypodensity on the left basal ganglia. He became comatous and died immediately after discharge. Until now in Korea, two cases that are described in this paper, one Acanthamoeba meningoencephalitis case and seven Acanthamoeba keratitis cases including two unreported keratitis cases that are reported in this paper have been presented.