Functional and Structural Studies of Small Bowel in Ankylostomiasis

Abstract

Non-specific Haemorrhagic Proctocolitis-Riis et al. MEDICALJOURThe main reason for discrepancy between the two methods of evaluation thus seems to be a difference of threshold. SummarySixty-five episodes of complete clinical remission in 46 patients with a verified diagnosis of non-specific haemorrhagic proctocolitis were studied with respect to macroscopic and microscopical signs of mucosal inflammation.The microscopical evaluation was based on the cytological method described in a previous paper. Macroscopic assessment was made by sigmoidoscopy with the use of conventional criteria.In 31 episodes sigmoidoscopy revealed macroscopically abnormal mucosas; in 24 of these the cytological preparations also showed inflammatory changes, while the cytological pictures were normal in seven. In the remaining 34 episodes no mucosal changes were found at sigmoidoscopy; in 16 of these distinct inflammation was seen microscopically, while normal cytology was demonstrated in 18.In about two-thirds of the episodes of patients with remissions shorter than six months the cytological method showed inflammatory changes, whereas the corresponding proportion in remissions of more than six months' duration was only slightly over two-fifths.The ability of microscopical techniques-like the cytological method used in the present investigation-to demonstrate unequivocal signs of inflammation in proctocolitis patients who are in full clinical remission, and who may even show a normal sigmoidoscopical picture, can be utilized diagnostically when such patients are first seen in a symptom-free or symptom-poor phase. The fact also points to the latent chronicity of nonspecific haemorrhagic proctocolitis and calls for circumspection with regard to the prognosis of the disease.

Present Status of Subclinical Intestinal Malabsorption in the Tropics

“…Also, similar morphological changes of the intestinal mucosa have been described in a variety of clinical situations, including overt tropical sprue (Butterworth and Perez-Santiago, 1958;Chacko et al, 1961;Baker et al, 1962;Falaiye, 1970), kwashiorkor (Burman, 1965;Stanfield et al, 1965), hookworm disease in India (Tandon et al, 1966), and rosacea (Watson et al, 1965). It is clear therefore that these histological changes do not have any diagnostic significance when taken alone.…”

“…Parasitic Infestations.-It has been recognized that certain parasitic infestations of the gastrointestinal tract, particularly with heavy loads of Strongyloides stercoralis (Milner et al, 1965), Ciardia lamblia (Amini, 1963), and hookworm disease in India (Tandon et al, 1966(Tandon et al, , 1969, may disrupt mucosal structure and function in the small bowel. In the two studies frcm Africa relating to hookworm disease and intestinal absorptive capacity Gilles et al (1964) and Banwell et al (1967) could not find any association between infestation with this parasite and intestinal malabsorption.…”

Molecular mechanisms of hookworm disease: Stealth, virulence, and vaccines

“…85,86 It has been suggested that the neutralization of digestive proteases by hookworm-derived, broad-spectrum protease inhibitors, although protecting the parasite from the proteolytic environment of the small intestine, contributes to malnourishment and impairment of physical growth by interfering with the intestinal absorption of nutrients. 87 In support of this theory, hamsters immunized with AceKI-1 and then challenged with A ceylanicum hookworms were partially protected against hookworm-associated growth delay without a measureable effect on anemia, suggesting that the prevention of growth delay is due to downstream effects of antibody-mediated neutralization of protease inhibitors and not directly related to parasite death.…”

Molecular Characterization ofAncylostoma ceylanicumKunitz-Type Serine Protease Inhibitor: Evidence for a Role in Hookworm-Associated Growth Delay

“…While the anemia is presumably due to the cumulative effect of chronic intestinal blood loss, the molecular mechanisms underlying the pathogenesis of hookworm malnutrition remain unknown. Although it has been suggested that hookworm malnutrition and growth delay occur secondary to chronic iron deficiency, particularly in children, evidence from prior clinical studies suggests that hookworm infection is also associated with various degrees of intestinal malabsorption (18,35,54,57,62). It has been hypothesized that this hookworm malabsorption syndrome might occur secondary to mucosal inflammation triggered by the adult worm attached to the intestinal epithelium or might be a result of secretion of parasite inhibitors of host digestive enzymes (18).…”