Clinical epidemiology and classification of human oesophagostomiasis

Abstract

The intestinal helminth Oesophagostomum bifurcum is highly and focally endemic in northern Ghana and Togo, and its juveniles produce a nodular inflammatory response as they develop in the intestinal wall. This pathology can produce clinical symptoms. We report on 156 cases of oesophagostomiasis presenting in 1996-98 to Nalerigu hospital in northern Ghana. The disease accounted for 0.2% of the out-patient department new presentations (about 1 patient per week), and 1% (16) of the major acute surgical cases. Children aged 5-9 years were most commonly affected. Multinodular disease (13% of the cases) results from hundreds of pea-sized nodules within the colon wall and other intra-abdominal structures, and presents with general abdominal pain, persistent diarrhoea and weight loss. Dapaong tumour (87%) presents as an abdominal inflammatory mass often associated with fever. The 3-6-cm tumour is painful, well-delineated, smooth, spherical, 'wooden', periumbilical, and adhered to the abdominal wall. Cases most commonly presented during the late rains and early dry season. Diagnosis by ultrasound has reduced the need for exploratory surgery, and the ability to sonographically evaluate conservative treatment with albendazole has curtailed management by colectomy or incision and drainage.

Human oesophagostomiasis: a histomorphometric study of 13 new cases in northern Ghana

“…These masses are recognised by the native people themselves and are well known in the local culture [21]. They can cause localised abdominal pain and discomfort, commonly in the right lower quadrant.…”

“…The bowel wall is diffusely hardened, and the surgical differential diagnosis is often against inflammatory bowel disease or even carcinoma. In the unilocular form a ligneous mass 30-60 mm in diameter is found [21]. In northern Ghana oesophagostomiasis accounts for approximately 1% of the annual major surgical procedures and 0.2% of patient contacts [20].…”

Intraobserver and interobserver variation of ultrasound diagnosis of Oesophagostomum bifurcum colon lesions.

“…Its usefulness to monitor colonic recovery after treatment with albendazole has been described. 3 Ultrasound can contribute significantly to the diagnosis of esophagostomiasis in northern Ghana because all regional hospitals have recently been equipped with highquality equipment and local personnel have been trained.…”

“…The lesions contain thick yellow pus and a white, living Oesophagostomum worm approximately 11 mm in length. 3 Patients can present with the so-called Dapaong tumor, a painful abdominal mass, 30-60 mm in diameter, which is frequently adherent to the abdominal wall. Peritonitis secondary to nodule rupture, bowel obstruction secondary to inflammatory adhesions, and the formation of cutaneous abscesses and fistulas can result.…”

“…However, estimation of the sensitivity and specificity of the ultrasound diagnosis of O. bifurcum pathology cannot be made because when the ultrasound appearance of the pathology was described, 10 surgical diagnosis and management were superseded by conservative chemotherapeutic treatment, followed by ultrasound to monitor colonic recovery. 3 Sonography can be considerably handicapped by observer bias, regardless of formalized diagnostic criteria. Subjectivity is an inherent characteristic of ultrasound, not only in the real-time appraisal of the findings, but also in the decision as to which view to represent photographically.…”