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.

Spectrum of amebiasis in children

In 11 patients with childhood amebiasis, only two had dysentery. Additional clinical findings included hematochezia without diarrhea (four patients), dysentery with appendicitis (one patient), exacerbation of ulcerative colitis (two patients), and disseminated infantile amebiasis (two patients). All patients with hematochezia examined by proctosigmoidoscopy had colitis. The diagnosis of amebiasis was confirmed by microscopic examination of fresh stool specimens, pathologic findings, and/or serologic titers. Amebiasis should be considered in the differential diagnosis of infants and children with hematochezia or hepatomegaly, especially in endemic areas.

Cytologic detection of parasitic disorders

Parasitic diseases are common in developing countries; yet they are infrequently diagnosed in cytologic material. Six cases are described where routine cytologic examination identified the parasites and suggested the diagnosis. There were three cases of Entamoeba histolytica infection of the female genital tract and one each of hydatid cyst of the brain, Strongyloides stercoralis infection of the lung and filarial infection of the urinary bladder. To our knowledge, cytologic diagnosis of hydatid cyst of the brain and filarial infection of the urinary bladder has not been previously reported.

Comparison of indirect fluorescent-antibody amoebic serology with counterimmunoelectrophoresis and indirect hemagglutination amoebic serologies

Patients ranged from those with no prior diagnosis of or suspected exposure to Entamoeba histolytica to those with proven amoebic liver abscesses (extraintestinal disease). A comparison of serologies from patients with proven and suspected amoebiasis or possible past exposure revealed good correlation between the indirect fluorescent antibody (IFA) procedure and the other methods used, counterimmunoelectrophoresis and indirect hemagglutination. Titers from patients with proven extraintestinal amoebiasis were in the expected high range previously reported by other authors. Patients with clinical histories suggestive of exposure to E. histolytica but no proven disease had lower titers which indicated possible background exposure. The IFA procedure provides a rapid method of antibody detection; results obtained on an emergency basis provide essential information in making the diagnosis of amoebic abscess, pyogenic abscess, or tumor. The IFA procedure is rapid, reliable reproducible, and relatively inexpensive to perform, provided a good source of antigen is consistently available.

[Pleuropulmonary manifestations in amebiasis. Sixty-one cases seen in Abidjan over a three-year period (author's transl)]

Sixty-one observations of pleuropulmonary amebiasis are reported with a detailed analysis of radioclinical features In 13.1% of the cases there were no clinical signs of associated hepatic involvement. Diagnostic difficulties were encountered in 42.6% of the cases which were suggestive of bacterial pleuropulmonary disease, tuberculosis or carcinoma. Serologic tests for amebiasis, which were positive in 95% of the cases, are very helpful diagnostic tools. Metronidazole and its derivatives were used in 80% of the cases with satisfactory results: death occurred in 3.5% of the cases and good short-term results in 84.6%. Sequelae were mainly observed after amebic empyema which resulted in chronic pleural disorders in 27.7% of the cases.

Preliminary observations using a multi-layer ELISA method for the detection of Entamoeba histolytica trophozoite antigens in stool samples

A method for detecting Entamoeba histolytica trophozoite antigens in aqueous solution is described. This involves coating plastic microtitre plates with a 'catching antibody', specific rabbit anti-E. histolytica antibody (SRAE). After adding the test material the presence of antigen is determined using two additional heterologous antibody layers, one of 'developing antibody', in this case human anti-E. histolytica immunoglobulin (HAE), which is followed by a final layer of peroxidase conjugated sheep anti-human immunoglobulin antibody (SH-HRP). The specificity and sensitivity of the assay was investigated both in the model system and using stool samples from infected patients. In the model system, the test had a sensitivity equivalent to detection of approximately one amoeba per microscope coverslip (18 mm X 18 mm). Little cross reaction was observed with other intestinal parasites common to the area of Bangladesh from which the stool samples were taken. The possible use of this method in large scale screening of stool samples and in the detection of circulating antigens is discussed.

Chronic amebic meningoencephalitis

A patient had a five-year history of sleep disturbance that culminated in a confusional illness with convulsions from which he made a partial recovery. On three separate occasions, the same ameba (Hartmannella rhysodes) was seen in and cultured from the patient's CSF. There was a rising serum titer of immobilizing antibody against the isolated strain of the ameba. The diagnosis of chronic amebic meningoencephalitis was considered in this patient.

[Differential diagnosis of colitis]

The differential diagnostic possibilities in colitic changes are presented. In addition, the specific objectives of major examination procedures in the differentiation of the underlying diseases are indicated. In this connection, mention is also made of the etiopathogenic factors-in those conditions in which they are known with certainty.