Primary amoebic meningoencephalitis: a first reported case in Thailand

A case of primary amoebic meningoencephalitis caused by Naegleria, from Sisaket province of Thailand is first reported. A 5-year old Thai with boy a history of swimming in a pond along a rice field before the onset of this illness, was admitted to the provincial hospital for chief complaints of headache, high fever, vomiting and drowsiness for 4 days. On admission he had convulsions and became comatosed with signs of meningeal irritation. The cerebrospinal fluid was similar to pyogenic meningitis but numerous amoebae were found and identified as Naegleria sp. Unfortunately, specific treatment was not administered promptly, the patient died 3 days after admission.

Cytopathologic diagnosis of extracolonic amebiasis

Extracolonic amebiasis must be distinguished from bacterial abscesses and neoplastic disease. Newer technology in diagnostic and interventional radiology permits such lesions to be aspirated more accurately for both diagnostic and therapeutic purposes, often averting an open surgical procedure. Paracecal and hepatic masses of one patient, who presented with fever and abdominal pain, were shown to be amebic abscesses by cytopathologic examination of material obtained by ultrasonically guided percutaneous fine needle aspiration. Another patient, who was thought to have metastatic carcinoma, died, with clinically unrecognized extensive pulmonary and hepatic amebiasis proven at autopsy. A review of this patient's sputum cytology smears showed numerous trophozoites of Entamoeba histolytica that were not recognized earlier. Cytopathologic studies of sputum and fine needle aspirates is an important means of detecting extracolonic amebiasis and distinguishing these lesions from neoplastic disease.

Amebiasis in Canada

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Infectious colitis endoscopically simulating inflammatory bowel disease: a prospective evaluation

This prospective evaluation of patients presenting with mucoid bloody diarrhea and suspected idiopathic inflammatory bowel disease demonstrated a 38% incidence of infectious colitides. The infectious agents detected were Campylobacter, Salmonella, Shigella, Amoeba, and Clostridium difficile. An increased awareness and the utilization of selective culture media should allow the clinician to definitively diagnose patients who present with signs and symptoms suggestive of idiopathic inflammatory bowel disease.

Parasitic rheumatism presenting as rheumatoid arthritis

A symmetrical polyarthritis with low titer positive rheumatoid factor occurred in a young man who also complained of chronic diarrhea after returning from Vietnam. Endolimax nana grew on stool culture. Both the patient's diarrhea and arthritis responded effectively to therapy with metronidazole. The diagnosis of parasitic rheumatism was made in retrospect. Diagnostic consideration should be given to this entity in patients with unusual arthropathies, particularly if they have stayed in an endemic parasitic country and have gastrointestinal symptoms.

Cutaneous amebiasis

An infant with cutaneous amebiasis of the vulva and amebic liver abscess is described. Epidemiologic investigations and serologic studies were crucial in establishing the diagnosis. The vulvar amebic ulcers responded dramatically to metronidazole therapy. Cutaneous amebiasis is a rare complication of Entamoeba histolytica infection which should be considered in the differential diagnosis of perineovulvar or penile ulcers. Cutaneous amebiasis may also occur on the abdominal wall surrounding a draining hepatic abscess, colostomy site, or laparotomy incision.

[Parasitic diarrheas]

The role of parasites as etiologic agents in diarrhoea is emphasized. In countries of Western Europe, Entamoeba histolytica and Giardia lamblia are the most prevalent species, although some other 20 protozoans and helminths may lead to diarrhoeic disturbances. Parasitology, pathogenesis, clinical signs, diagnosis, and therapy are briefly outlined. The need for competence on the part of the personnel responsible for laboratory diagnosis is emphasized; also, newly developed immunodiagnostic methods may render appreciable services in doubtful cases. Adequate therapy yields successful results in over 90% of the cases.

Amoebic meningitis also occurs in NSW

The clinical, pathological and laboratory findings of a 3-year-old boy with proven primary amoebic meningo-encephalitis are described. The EEG showed changes of acute cortical necrosis lateralised to one temporal lobe and was similar to that described with Herpes simplex encephalitis. CT scan findings indicated acute cortical inflammation and basal arachnoiditis. The disease should be suspected in the context of acute pyogenic meningitis when no organisms are isolated. Treatment with amphotericin-B, miconazole and rifampicin has been effective in previously reported patients.

Primary amebic meningoencephalitis diagnosed in the emergency department

Reported is a case of primary amebic meningoencephalitis diagnosed in the emergency department. The patient, a previously healthy teenager, developed Naegleria meningoencephalitis after swimming in a freshwater public pool. The Naegleria caused acute fulminating infection culminating in the death of the patient 36 hours after admission. Results of a spinal tap, together with the history of swimming in warm fresh water, led to the emergency department diagnosis.

A solid-phase sandwich radioimmunoassay for Entamoeba histolytica proteins and the detection of circulating antigens in amoebiasis

A sensitive and specific immunochemical assay for Entamoeba histolytica antigens would be a valuable tool for clinical diagnosis, to study the sequelae of amoebiasis, and to screen for the expression of amoebic proteins in recombinant bacterial clones. The major impediment toward developing such an assay is the cross-reactivity of anti-E. histolytica antisera with a wide range of mammalian serum proteins. A rabbit anti-E. histolytica antiserum was repeatedly passed over three bovine serum protein immunoadsorbents and affinity purified over an E. histolytica protein-Sepharose 4B matrix. The purified antibody was radiolabeled and formed the upper layer of two specific and sensitive sandwich radioimmunoassays for amoebic proteins. One assay used a rabbit antiamoebic antibody solid phase and the other a human antibody solid phase. The latter assay proved capable of detecting amoebic antigens in the polyethylene glycol precipitates of sera from 21 of 21 patients with amoebiasis (and none of 22 control subjects).

Hepatopulmonary amebiasis--a review of 40 cases

Forty cases of hepatopulmonary amebiasis secondary to hepatic amebiasis are reported. In an endemic area of amebiasis, this entity should always be borne in mind, as the frequent reports of hepatopulmonary amebiasis gives evidence of the magnitude of the problem. Diagnosis is mainly based on a palpable tender liver and/or lower intercostal tenderness, the fluoroscopic and radiological findings, and therapeutic response to dehydroemetine.

Pseudomalignant cutaneous amoebiasis

Two cases of cutaneous amoebiasis which presented as malignant ulcers are reported. In non-healing ulcers in the perianal or gluteal region, the possibility of amoebiasis should be kept in mind, especially in the tropics. An immediate examination of the scraping from the ulcer is sufficient to confirm or rule out the diagnosis.