- Email: [email protected]
Rectal snips in the diagnosis of hepatosplenic schistosomiasis
720 Katz, N., Rocha,R. S. & Chaves,A. (1979).Preliminary trials with praziquantel in human infections due to Schiswsomamansoni.Bulletin of the World Health Organization. 57, 781-78.
Pearson,R. D. & Guerrant,R. L. (1983).Praziquantel:a
major advancein anthelminthic therapy. Annuls of
Internal Medicine, 99, 195-198. Received 17 February accepted fm publicat&
1988; revised 3 May 10 May 1988 -
1988: ”
T~~~slrcrro~sOFTHEROYALSOCKIT OF TROPICALMEDICINE AND HYGIENE(1988) 82, 720
IShort
Report 1
Table-Parasitology findiigs and siteof rectalmucosalbiopsy in patients with S. mans& infection Rectal wall
Rectal snips in the diagnosis of hepatosplenic schistosomiasis Antony D. Harries’ and Richard Speare Department of Medicine, Kamuzu Central Hospital, P.O.Box 149, Lilongwe, Malawi
In patients with suspectedintestinal or hepatosplenit schistosomiasisova of Schistosoma mans& may be found in snips of rectal mucosa when repeated examinations of faecal smears are negative (WARD, 1977; HARRIES et al., 1986). There is, however, no information on the number of rectal snips needed for diagnosis. In somecentres 3 (ARAFAet al., 1983), and in others 4 (HARRIES et al., 1986), rectal snips are taken for diagnostic purposes, whereas in Malawi it has been routine clinical practice to take one rectal snip, usually from the anterior rectal wall. We decided therefore to carry out a prospective study to determine whether increasing the number of rectal snips from one to 4 increased the diagnostic yield. il0 Malawian adults (60 men and 50 women,mean age + SD=34?11 vears) were studied. Thev were sispected clinically io have hepatosplenic s&istosomiasis, but direct faecal smearsfor ova of S. mansuni were negative. Splenomegaly (median size 10 cm below the left costal margin) was present in all patients, hepatomegaly in 63, ascites in 26 and oesophageal varices (on endoscopy) in 22. Proctoscopy was performed on each patient in the left lateral position, and 4 snips of rectal mucosa (l-2 mm in size) were obtained with a Harrison curette. Snips were taken from the following sites on the rectal wall: anterior, right lateral, posterior and left lateral. Specimens were pressed between 2 slides and examined microscopically by both of us. A record was made of specimenscontaining ova of S. mansoni, and the number of ova per specimen was counted. Rectal snips from 57 patients contained ova of S. munsoni.4 positive snips were obtained from 21(37%) patients, 3 positive and one negative from 12 (21%), 2 positive and 2 negative from 9 (16%), and one positive and 3 negative from 15 (26%). Using 4 rectal snips as the diagnostic standard in’ the patients with S. munsoni, 4 snips were diagnostic in all cases, 3 snips were diagnostic in 42 (74%), 2 snips were diagnostic in 33 (58%) and one snip was diagnostic in 21 (37%). ‘Author for correspondence on secondrnentfrom the Liverpool Schoolof Tropical Medicine, UK.
Anterior Number (%) of rectal snips positive for s. mansoni ova 34W)
RightlateralPosteriorLeft lateral 39(68)
42(74)
38(67)
Median (range) number of S. mmmi ova iu each rectal Snip 4(1-l%)
7(1-57)
q1-37)
7(1-126)
There wss no significant difference between sites of rectal mucosal biopsy in termsof(i) numberof positiverectalsnips(x2test),or (ii) number of ova in each specimen (Mann-Whitney U test).
In patients with S. mansoni there was a similar number of positive specimens from each of the 4 biopsy sites, and the number of ova found in specimens from each of the 4 sites was also similar (Table). Although there were no complications from the prdcedures,h 2 patients with oesiphageal vari& brisk bleeding followed the bioDsv but this WV controlled by-firm pressure with-a-gauze swab for 10 min. This study confirms the value of rectal mucosal snips in the diagnosis of S. mansoni infection in patients from whom direct faecal smearsare negative. The site of biopsy was unimportant in terms of diagnostic yield, but results clearly indicate that increasing the number of rectal snips from one to 4 does increase the number of diagnoses. It is possible that more than 4 rectal snips would result in an even higher diagnostic yield, but we feel in routine clinical practice that 4 snips is about the limit of tolerance for both the patient and the clinician. Although care needs to be taken in patients known to have portal hypertension the procedure is safe, and we suggest that 4 rectal smps be routinely obtained from patients with suspectedS . mansoni infection from whom direct faecal smears are unhelpful. References
Arafa,M. S., Hamadto,H. A. & El Ridi, A. M. S. (1983).A stidy of &therectalsnip transparencyand Karo techni: quesin diagnosisof intestinalschistosomiasis. Journal of the Egyptian Society of Parasitology, 13, 373-378.
Harries, A. D., Fryatt, R., Walker, J., Chiodi$ P. L. & Bryceson,A. D. M. (1986).Schistosomiasis m expatriates returning to Britain from the tropics: a controlled study. Lance;, i, 86-88.
Ward, J. C. (1977).Rectumand stool in schistosomiasis. American 3ournal of Medicine, 62, 162.
Received 12 Apti1 1988; accepted for publication 27 April 1988
Pearson,R. D. & Guerrant,R. L. (1983).Praziquantel:a
major advancein anthelminthic therapy. Annuls of
Internal Medicine, 99, 195-198. Received 17 February accepted fm publicat&
1988; revised 3 May 10 May 1988 -
1988: ”
T~~~slrcrro~sOFTHEROYALSOCKIT OF TROPICALMEDICINE AND HYGIENE(1988) 82, 720
IShort
Report 1
Table-Parasitology findiigs and siteof rectalmucosalbiopsy in patients with S. mans& infection Rectal wall
Rectal snips in the diagnosis of hepatosplenic schistosomiasis Antony D. Harries’ and Richard Speare Department of Medicine, Kamuzu Central Hospital, P.O.Box 149, Lilongwe, Malawi
In patients with suspectedintestinal or hepatosplenit schistosomiasisova of Schistosoma mans& may be found in snips of rectal mucosa when repeated examinations of faecal smears are negative (WARD, 1977; HARRIES et al., 1986). There is, however, no information on the number of rectal snips needed for diagnosis. In somecentres 3 (ARAFAet al., 1983), and in others 4 (HARRIES et al., 1986), rectal snips are taken for diagnostic purposes, whereas in Malawi it has been routine clinical practice to take one rectal snip, usually from the anterior rectal wall. We decided therefore to carry out a prospective study to determine whether increasing the number of rectal snips from one to 4 increased the diagnostic yield. il0 Malawian adults (60 men and 50 women,mean age + SD=34?11 vears) were studied. Thev were sispected clinically io have hepatosplenic s&istosomiasis, but direct faecal smearsfor ova of S. mansuni were negative. Splenomegaly (median size 10 cm below the left costal margin) was present in all patients, hepatomegaly in 63, ascites in 26 and oesophageal varices (on endoscopy) in 22. Proctoscopy was performed on each patient in the left lateral position, and 4 snips of rectal mucosa (l-2 mm in size) were obtained with a Harrison curette. Snips were taken from the following sites on the rectal wall: anterior, right lateral, posterior and left lateral. Specimens were pressed between 2 slides and examined microscopically by both of us. A record was made of specimenscontaining ova of S. mansoni, and the number of ova per specimen was counted. Rectal snips from 57 patients contained ova of S. munsoni.4 positive snips were obtained from 21(37%) patients, 3 positive and one negative from 12 (21%), 2 positive and 2 negative from 9 (16%), and one positive and 3 negative from 15 (26%). Using 4 rectal snips as the diagnostic standard in’ the patients with S. munsoni, 4 snips were diagnostic in all cases, 3 snips were diagnostic in 42 (74%), 2 snips were diagnostic in 33 (58%) and one snip was diagnostic in 21 (37%). ‘Author for correspondence on secondrnentfrom the Liverpool Schoolof Tropical Medicine, UK.
Anterior Number (%) of rectal snips positive for s. mansoni ova 34W)
RightlateralPosteriorLeft lateral 39(68)
42(74)
38(67)
Median (range) number of S. mmmi ova iu each rectal Snip 4(1-l%)
7(1-57)
q1-37)
7(1-126)
There wss no significant difference between sites of rectal mucosal biopsy in termsof(i) numberof positiverectalsnips(x2test),or (ii) number of ova in each specimen (Mann-Whitney U test).
In patients with S. mansoni there was a similar number of positive specimens from each of the 4 biopsy sites, and the number of ova found in specimens from each of the 4 sites was also similar (Table). Although there were no complications from the prdcedures,h 2 patients with oesiphageal vari& brisk bleeding followed the bioDsv but this WV controlled by-firm pressure with-a-gauze swab for 10 min. This study confirms the value of rectal mucosal snips in the diagnosis of S. mansoni infection in patients from whom direct faecal smearsare negative. The site of biopsy was unimportant in terms of diagnostic yield, but results clearly indicate that increasing the number of rectal snips from one to 4 does increase the number of diagnoses. It is possible that more than 4 rectal snips would result in an even higher diagnostic yield, but we feel in routine clinical practice that 4 snips is about the limit of tolerance for both the patient and the clinician. Although care needs to be taken in patients known to have portal hypertension the procedure is safe, and we suggest that 4 rectal smps be routinely obtained from patients with suspectedS . mansoni infection from whom direct faecal smears are unhelpful. References
Arafa,M. S., Hamadto,H. A. & El Ridi, A. M. S. (1983).A stidy of &therectalsnip transparencyand Karo techni: quesin diagnosisof intestinalschistosomiasis. Journal of the Egyptian Society of Parasitology, 13, 373-378.
Harries, A. D., Fryatt, R., Walker, J., Chiodi$ P. L. & Bryceson,A. D. M. (1986).Schistosomiasis m expatriates returning to Britain from the tropics: a controlled study. Lance;, i, 86-88.
Ward, J. C. (1977).Rectumand stool in schistosomiasis. American 3ournal of Medicine, 62, 162.
Received 12 Apti1 1988; accepted for publication 27 April 1988