Abstract
Thickening of the internal anal sphincter (IAS) is observed in chronic idiopathic constipation (IC) and solitary rectal ulcer syndrome (SRUS), where it has been correlated with the presence and severity of rectal intussusception. Alternatively, thickened IAS may be a feature of the obstructed megarectum in a similar way to the hypertrophy of bladder neck seen in dyssynergic bladders. The aim of this study was to investigate the significance of thickening of the IAS in children with chronic IC and to determine any association between the thickened IAS and anorectal manometry findings and patient’s symptoms. A total of 144 children were admitted for investigations and treatment of chronic IC and evaluated prospectively between April 2001 and April 2003. IAS thickness was measured by endosonography using B&K axial endosonic probe type 1850 with a 10-MHz rotating transducer. The thickness of IAS was measured at 3, 6, and 9 o’clock, and the mean value of the three measurements was used for analysis. Functional assessment was done by anorectal manometry pressure studies under ketamine anaesthesia. A validated symptom score (SS) was used to assess the severity of symptoms. The sum of SS ranged between 0 and 65. Spearman’s rho two-tailed test was used to correlate the thickness of IAS with patients’ symptoms and anorectal manometry findings. Results were expressed as median and range and p-value of less than 0.05 was considered significant. Of 144 children, 84 were boys, median age 8.1 years (range 3.1–15). Soiling was present in 137 (94%) patients, delay in defecation in 132 (91%), and a palpable megarectum on abdominal examination in 117 (80%). The median duration of symptoms and duration of laxative treatment were 4 years (range 0.3–14.5) and 3.3 years (0.2–13.5), respectively. The average severity score for soiling, delay in defecation, palpable megarectum, and the total SS were 8 (range 0–10), 5 (0–10), 2 (0–12), and 33 (11–51), respectively. The median thickness of IAS was 0.9 mm (range 0.3–2.8) and the median resting anal sphincter pressure was 54 mmHg (19–107). The median amplitudes of rectal and anal sphincter contraction were 3 mmHg (1–25) and 9 mmHg (1–35), respectively. The thickness of IAS correlated significantly with total symptom severity score (r=0.31, p=0.0001), soiling score (r=0.28, p=0.001), megarectum score on abdominal palpation (r=0.29, p=0.001), size of megarectum on manometry (r=0.36, p=0.0001), amplitude of rectal contraction (r=0.23, p=0.007), and age of patient (r=0.55, p=0.0001). There was also a significant correlation between the amplitude of rectal and anal sphincter contraction (r=0.32, p=0.0001). There was no correlation between thickness of IAS and resting anal sphincter pressure and amplitude of anal sphincter contraction on anorectal manometry study. A total of 24 children had myectomy of thickened and overactive IAS in addition to the medical treatment of their chronic IC. The histology examination of myectomy specimen with eosin and haematoxylin staining and histochemical acetylcholine esterase staining showed smooth muscle fibres and ganglion cells. Thickening of IAS correlates significantly with duration and severity of symptoms, size of megarectum, and amplitude of rectal contraction. The pathogenesis is secondary to the continuous presence of faeces in the rectum, resulting in chronic abnormal stimulus to the IAS, which leads to hypertrophic changes in the rectum wall and IAS.
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References
Bartram CI, Frudinger A (1997) Handbook of anal endosonography. Wrightson Biomedical Publishing, Petersfield, UK
Bartram CI, Sultan AH (1995) Anal endosonography in faecal incontinence. Gut 37:4–6
Benninga MA, Wijers OB, van der Hoeven CW, Taminiau JA, Klopper PJ, Tytgat GN, Akkermans LM (1994) Manometry profilometry, and endosonography: normal physiology and anatomy of the anal canal in healthy children. J Pediatr Gastroenterol Nutr 18:68–77
Clayden GS, Lawson JON (1976) Investigation and management of long-standing chronic constipation in childhood. Arch Dis Child 51:918–923
Clayden GS, Keshtgar AS (2004) The use of a parent-completed symptom severity score in chronic childhood constipation and soiling (paper submitted for publication)
Callaghan RP, Nixon HH (1964) Megarectum: physiological observations. Arch Dis Child 39:153–157
Denny-Brown D, Robertson EG (1935) An investigation of the nervous control of defecation. Brain 58:256
Diamant NE, Kamm MA, Wald A, Whitehead WE (1999) American gastroenterological association medical position statement on anorectal testing techniques. Gastroenterology 116:732–760
Duthie HI, Watts JM (1965) Contribution of the external anal sphincter to the pressure zone in the anal canal. Gut 6:64–68
Frenckner B, Euler CH (1975) Influence of pudendal block on the function of the anal sphincters. Gut 16:482–489
Gantke B, Schafer A, Enck P, Lubke HJ (1993) Sonographic, manometric, and myographic evaluation of the anal sphincters morphology and function. Dis Colon Rectum 36:1037–1041
Gibbons CP, Trowbridge EA, Bannister JJ, Read NW (1986) Role of anal cushions in maintaining continence. Lancet 1:886–887
Hosie GP, Spitz L (1997) Idiopathic constipation in childhood is associated with thickening of the internal anal sphincter. J Pediatr Surg 32:1041–1044
Keshtgar AS, Sanei A, Ward HC (2003) Manometry data analysis for windows in clinical practice. Presented in the 15th international research symposium in pediatric surgery, Marseille, 3–4 October 2003
Lesta B, Penninckx F, Kerremans R (1989) The composition of anal basal pressure. An in vivo and in vitro study in man. Int J Colorectal Dis 4:118–122
Loening-Bauke V (1993) Constipation in early childhood: patient characteristics, treatment, and longterm follow up. Gut 34:1400–1404
Loening-Bauke VA (1984) Abnormal rectoanal function in children recovered from chronic constipation and encopresis. Gastroenterology 87:1299–1304
Marshall M, Halligan S, Fotheringham T, Bartram C, Nicholls RJ (2002) Predictive value of internal anal sphincter thickness for diagnosis of rectal intussusception in patients with solitary rectal ulcer syndrome. Br J Surg 89:1281–1285
Meunier P, Marechal JM, DeBeaujeu MJ (1979) Rectoanal pressures and rectal sensitivity studies in chronic childhood constipation. Gastroenterology 71:774–779
Nixon HH (1967) Megarectum in the older child. Proc R Soc Med 60:29–31
Papadopoulou A, Clayden GS, Booth IW (1994) The clinical value of solid marker transit studies in childhood constipation and soiling. Eur J Pediatr 153:560–564
Paskins JR, Lawson JON, Clayden GS (1984) The effect of ketamine anesthesia on anorectal manometry. J Pediatr Surg 19:289–291
Plas van der RN, Benninga MA, Buller HA, Bossuyt PM, Akkermans LMA, Redekop WK, Taminiau JA (1996) Biofeedback training in treatment of childhood constipation: a randomised controlled study. Lancet 348:776–780
Schuster MM, Hookman P, Hendrix TR, Mendeloff AI (1965) Simultaneous manometric recording of internal and external anal sphincter reflexes. Bull Johns Hopkins Hosp 116:79
Schweiger M (1979) Method for determining individual contributions of voluntary and involuntary anal sphincters to resting tone. Dis Colon Rectum 22:415–416
Sultan AH, Kamm MA, Nicholls RJ, Bartram CI (1994) Prospective study of the extent of internal anal sphincter division during lateral sphincterotomy. Dis Colon Rectum 37:1031–1033
Sultan AH, Kamm MA, Hudson CN, Nicholls JR, Bartram CI (1994) Endosonography of the anal sphincters: normal anatomy and comparison with manometry. Clin Radiol 49:368–374
Sultan AH, Kamm MA, Talbot IC, Nicholls RJ, Bartram CI (1994) Anal endosonography for identifying external sphincter defects confirmed histologically. Br J Surg 81:463–465
Sun WM, Read NW, Donelly TC, Bannister JJ, Shorthouse AJ (1989) A common pathophysiology for full thickness rectal prolapse, anterior mucosal prolapse and solitary rectal ulcer. Br J Surg 76:290–295
Van Outryve MJ, Pelckmans PA, Fierens H, Van Maerke YM (1993) Transrectal ultrasound study of the pathogenesis of solitary rectal ulcer syndrome. Gut 34:1422–1426
Tjandra JJ, Milsom JW, Stolfi VM, Lavery I, Oakley J, Church J, Fazio V (1992) Endoluminal ultrasound defines anatomy of the anal canal and pelvic floor. Dis Colon Rectum 35:465–470
Tjandra JJ, Milsom JW, Schroeder T, Fazio VW (1993) Endoluminal ultrasound is preferable to electromyography in mapping anal sphincteric defects. Dis Colon Rectum 36:689–692
Wald A, Chandra R, Chiponis D, Gabel S (1987) Anorectal function and continence mechanisms in childhood encopresis. J Pediatr Gastroenterol Nutr 6:915–922
Yang YS, Kamm MA, Engel AF, Talbot IC (1996) Pathology of the rectal wall in solitary rectal ulcer syndrome and complete rectal prolapse. Gut 38:587–590
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Keshtgar, A.S., Ward, H.C., Clayden, G.S. et al. Thickening of the internal anal sphincter in idiopathic constipation in children. Ped Surgery Int 20, 817–823 (2004). https://doi.org/10.1007/s00383-004-1233-4
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DOI: https://doi.org/10.1007/s00383-004-1233-4