Primary Megarectum Associated with Imperforate Anus: Report
of a Case*
M. BERENGO, M.D., G. DonI, M.D., G. SEGATO,M.D., G. URBANI, M.D. Padua, Italy
MEGARECTUM is rarely associated with imperforate anus, and primary megarectum is even more rarely found in adult patients who in their first days of life had been operated on for anal malformations only. Report of a Case A 32-year-old farmer h a d a totally noncontributory family history. H e had been born at term, with a normal delivery. At birth he had had a low anal imperforation, for which he u n d e r w e n t immediate surgical anal reconstruction. Nevertheless, h e h a d continued to have obstinate constipation. In the following years painful subocclusive episodes were resolved with enemas and manual removal of fecalomas. Repeated cycles of anal dilatation did not alleviate the symptoms. Due to persistent constipation for three to six weeks and the appearance of abdominal colic with nausea and vomiting in past months, the patient was referred to our clinic. On examination the patient was found to be bradypsychic, in degenerating general condition. A diastolic aortic m u r m u r of 3/6 intensity was heard. T h e a b d o m e n was asymmetric due to a visible palpable tumefaction extending from the hypogastrium to the right hypochondrium. On palpation of the mass a lasting indentation remained. T h e anus was stenotic and did not permit introduction of the little finger. Barium.enema studies demonstrated a monstrously enlarged rectum with an enormous filling defect of a "fecal stasis" type (Fig. 1). Blood studies showed hypochromic anemia (erythrocytes 3,690,000; hemoglobin 9 . 3 g / 1 0 0 m l ; hematocrit 29 per cent) and leukocytosis (leukocyte count 10,700). T h e patient was treated by enemas and anal dilatation, using Hegar's dilators up to N. 20, these measures neither completely eliminated the enor-
]FIG. 1. Barium-enema study, showing a monstrously enlarged and elongated rectum reaching the epigastrium and right hypochondrium. mous fecalomas nor re-established normal peristalsis; therefore, surgical correction for suspected megarectum secondary to anal stenosis was decided upon. At operation, the rectum, the size of a watermelon, was found occupying a great part of the abdomen tip to the diaphragm, and containing very hard fecalomas (Fig. 2). It was necessary to open the megarectum and remove the fecal material. A classic D u h a m e l operation was performed, removing about 30 cm of intestine (Fig. 3). T h e postoperative course was normal, and a year after operation, the patient reported completely normal bowel habits. At that time, the anus was continent and nonstenotic. Biopsy of the removed segment showed slight chronic inflammation of the mucosa, marked hypertrophy of the tunica muscularis, few nerve fibers, and an absence of ganglia.
* Received for publication November 5, 1974. Address reprint requests to Dr. Urbani: II Divisione Chirurgica, Ospedale Civile di Padua, 35100 Padua, Italy.
699 Dis. Col. & Reet. Nov.-Dee. 1975
Volume 18 Nttmber 8
700
B E R E N G O , E T AL.
Dis. CoL & Rect. Nov.-Dee. 1975
Fro. 2. rectum,
The
abnormally
large
Discussion Megarectum can be secondary to anal stenosis, or it can be primary because of changes of the nerve structure 6 marked by absence, reduction, or degeneration of the intestinal wall ganglia. Since some normal subjects have been found to have an absence of nerve ganglia in short segments (not more than 13 mm)4 of the terminal rectum, such an absence must continue at least 2 cm above the anal verge to be a pathogenetically significant cause of primary megarectum. 4 In our patient the rectum was completely aganglionic for about 12 cm above the anal verge. Some investigators concede the possibility of iatrogenic aganglia?, s resulting from surgery, as in the operation of Swenson or the anoplastic operation for imperforate anus. In such cases, degenerative phenomena involving both the residual nerve structure and the vessel walls coexist with deposits of hyalin substance. In our case, the histologic examination did not clearly demonstrate degenerative aspects, but rather, showed a complete absence of ganglia, thus invalidating megarectum secondary to either anal stenosis or iatrogenic vascular alterations and substantiating imperforate anus associated with primary megarectum. T h e incidence of aganglionic megacolon (Hirschprung's disease) re-
FIG. 3.
Surgical specimen of intestine.
ported by Vanhoutte7 (1969) is one in 10,000 live births, while that of imperforate anus is one in 15,000. Only 8.4 per cent of cases of imperforate anus are accompanied by aganglia of at least 2 cm of the terminal segment of the colon. T h e unusual feature of our present case, apart from the plurimalformative picture
Volume 18 Number 8
MEGARECTUM W I T H IMPERFORATE ANUS
and the fact that the patient had suffered innumerable subocclusive episodes, is that he had reached the age of 32 years. Patients afflicted with primary megarectum or megacolon have secondary malabsorption due to compression and distortion of the small intestine by the fecal mass in the large intestine. 3 Frequently, as in this case, they have defective growth, hypochromic anemia, and psychic and sexual infantilism. T h e operation eliminated the aganglionic part of the intestine and the hyperdilated overlying segment, with restoration of normal function.2 In light of results obtained in the treatment of Hirschprung's disease with the Duhamel operation, resecting the entire enlarged tract, we deemed unnecessary to defunctionalize the colon for a few months with a temporary colostomy. Other investigators 2, 4 have reported relapses even after a Duhamel operation, with fecal stasis in the rectal cul-de-sac owing to hypertrophy of the external sphincter. In our case, after one year, the new ampulla did not manifest fecal slowing after emptying. T h e patient had gained weight and could engage in normal work activity.
701
Summary A case of primary megarectum in an adult patient operated upon many years after birth for imperforate anus is presented. Surgical treatment using a Duhamel operation resolved the chronic occlusive problem and normalized the general condition of the patient. References 1. Ehrenpreis T: Some newer aspects on Hirschsprung's disease and allied disorders. J Pediatr Surg 1: 329, 1966 2. Fairgrieve J: Hirschsprung's disease in the adult. Br J Surg 50: 506, 1963 3. Kempton JJ: Hirschsprung's disease in a man aged 23. Proc R Soc Med 47: 545, 1954 4. Kiesewetter WB, Sukarochana K, Sieber WK: The frequency of anganglionosis associated with imperforate anus. Surgery 58: 877, 1964 5. Riker WL: Diagnosis and treatment of aganglionosis of the myenteric plexus. Arch Surg 75: 362, 1957 6. Todd IP: Discussion on megacolon and megarectum with the emphasis on conditions other than Hirschsprung's disease. Proc R Soc Med 54: 1035, 1961 7. Vanhoutte JJ: Primary aganglionosis associated with imperforate anus: Review of the literature pertinent to one observation. J Pediatr Surg 4: 468, 1969
of a Case*
M. BERENGO, M.D., G. DonI, M.D., G. SEGATO,M.D., G. URBANI, M.D. Padua, Italy
MEGARECTUM is rarely associated with imperforate anus, and primary megarectum is even more rarely found in adult patients who in their first days of life had been operated on for anal malformations only. Report of a Case A 32-year-old farmer h a d a totally noncontributory family history. H e had been born at term, with a normal delivery. At birth he had had a low anal imperforation, for which he u n d e r w e n t immediate surgical anal reconstruction. Nevertheless, h e h a d continued to have obstinate constipation. In the following years painful subocclusive episodes were resolved with enemas and manual removal of fecalomas. Repeated cycles of anal dilatation did not alleviate the symptoms. Due to persistent constipation for three to six weeks and the appearance of abdominal colic with nausea and vomiting in past months, the patient was referred to our clinic. On examination the patient was found to be bradypsychic, in degenerating general condition. A diastolic aortic m u r m u r of 3/6 intensity was heard. T h e a b d o m e n was asymmetric due to a visible palpable tumefaction extending from the hypogastrium to the right hypochondrium. On palpation of the mass a lasting indentation remained. T h e anus was stenotic and did not permit introduction of the little finger. Barium.enema studies demonstrated a monstrously enlarged rectum with an enormous filling defect of a "fecal stasis" type (Fig. 1). Blood studies showed hypochromic anemia (erythrocytes 3,690,000; hemoglobin 9 . 3 g / 1 0 0 m l ; hematocrit 29 per cent) and leukocytosis (leukocyte count 10,700). T h e patient was treated by enemas and anal dilatation, using Hegar's dilators up to N. 20, these measures neither completely eliminated the enor-
]FIG. 1. Barium-enema study, showing a monstrously enlarged and elongated rectum reaching the epigastrium and right hypochondrium. mous fecalomas nor re-established normal peristalsis; therefore, surgical correction for suspected megarectum secondary to anal stenosis was decided upon. At operation, the rectum, the size of a watermelon, was found occupying a great part of the abdomen tip to the diaphragm, and containing very hard fecalomas (Fig. 2). It was necessary to open the megarectum and remove the fecal material. A classic D u h a m e l operation was performed, removing about 30 cm of intestine (Fig. 3). T h e postoperative course was normal, and a year after operation, the patient reported completely normal bowel habits. At that time, the anus was continent and nonstenotic. Biopsy of the removed segment showed slight chronic inflammation of the mucosa, marked hypertrophy of the tunica muscularis, few nerve fibers, and an absence of ganglia.
* Received for publication November 5, 1974. Address reprint requests to Dr. Urbani: II Divisione Chirurgica, Ospedale Civile di Padua, 35100 Padua, Italy.
699 Dis. Col. & Reet. Nov.-Dee. 1975
Volume 18 Nttmber 8
700
B E R E N G O , E T AL.
Dis. CoL & Rect. Nov.-Dee. 1975
Fro. 2. rectum,
The
abnormally
large
Discussion Megarectum can be secondary to anal stenosis, or it can be primary because of changes of the nerve structure 6 marked by absence, reduction, or degeneration of the intestinal wall ganglia. Since some normal subjects have been found to have an absence of nerve ganglia in short segments (not more than 13 mm)4 of the terminal rectum, such an absence must continue at least 2 cm above the anal verge to be a pathogenetically significant cause of primary megarectum. 4 In our patient the rectum was completely aganglionic for about 12 cm above the anal verge. Some investigators concede the possibility of iatrogenic aganglia?, s resulting from surgery, as in the operation of Swenson or the anoplastic operation for imperforate anus. In such cases, degenerative phenomena involving both the residual nerve structure and the vessel walls coexist with deposits of hyalin substance. In our case, the histologic examination did not clearly demonstrate degenerative aspects, but rather, showed a complete absence of ganglia, thus invalidating megarectum secondary to either anal stenosis or iatrogenic vascular alterations and substantiating imperforate anus associated with primary megarectum. T h e incidence of aganglionic megacolon (Hirschprung's disease) re-
FIG. 3.
Surgical specimen of intestine.
ported by Vanhoutte7 (1969) is one in 10,000 live births, while that of imperforate anus is one in 15,000. Only 8.4 per cent of cases of imperforate anus are accompanied by aganglia of at least 2 cm of the terminal segment of the colon. T h e unusual feature of our present case, apart from the plurimalformative picture
Volume 18 Number 8
MEGARECTUM W I T H IMPERFORATE ANUS
and the fact that the patient had suffered innumerable subocclusive episodes, is that he had reached the age of 32 years. Patients afflicted with primary megarectum or megacolon have secondary malabsorption due to compression and distortion of the small intestine by the fecal mass in the large intestine. 3 Frequently, as in this case, they have defective growth, hypochromic anemia, and psychic and sexual infantilism. T h e operation eliminated the aganglionic part of the intestine and the hyperdilated overlying segment, with restoration of normal function.2 In light of results obtained in the treatment of Hirschprung's disease with the Duhamel operation, resecting the entire enlarged tract, we deemed unnecessary to defunctionalize the colon for a few months with a temporary colostomy. Other investigators 2, 4 have reported relapses even after a Duhamel operation, with fecal stasis in the rectal cul-de-sac owing to hypertrophy of the external sphincter. In our case, after one year, the new ampulla did not manifest fecal slowing after emptying. T h e patient had gained weight and could engage in normal work activity.
701
Summary A case of primary megarectum in an adult patient operated upon many years after birth for imperforate anus is presented. Surgical treatment using a Duhamel operation resolved the chronic occlusive problem and normalized the general condition of the patient. References 1. Ehrenpreis T: Some newer aspects on Hirschsprung's disease and allied disorders. J Pediatr Surg 1: 329, 1966 2. Fairgrieve J: Hirschsprung's disease in the adult. Br J Surg 50: 506, 1963 3. Kempton JJ: Hirschsprung's disease in a man aged 23. Proc R Soc Med 47: 545, 1954 4. Kiesewetter WB, Sukarochana K, Sieber WK: The frequency of anganglionosis associated with imperforate anus. Surgery 58: 877, 1964 5. Riker WL: Diagnosis and treatment of aganglionosis of the myenteric plexus. Arch Surg 75: 362, 1957 6. Todd IP: Discussion on megacolon and megarectum with the emphasis on conditions other than Hirschsprung's disease. Proc R Soc Med 54: 1035, 1961 7. Vanhoutte JJ: Primary aganglionosis associated with imperforate anus: Review of the literature pertinent to one observation. J Pediatr Surg 4: 468, 1969
