Enzymhistochemie des klassischen und des ultrakurzen Morbus Hirschsprung

Hirschsprung's disease is the most important type of gastrointestinal dysmotility in neonatal pathology. Aberrant craniocaudal migration of neural crest stem cells results in an intestinal aganglionic segment of variable length. In 'classical' Hirschsprung's disease (60-75% of cases), the aganglionic segment spans the rectum and sigma. Ultrashort Hirschsprung's disease (5-10%) is restricted to the most distal 3-4 cm or immediate rectoanal transition only.In the normal enteric nervous system, myenteric ganglia modulate the parasympathetic innervation of the sacral roots S2-S4. The absence of myenteric ganglia in Hirschsprung's disease results in massively increased parasympathetic activity with abundant acetylcholine release and pseudo-obstruction in the aganglionic segment. This can be demonstrated in an enzyme histochemical reaction for acetylcholinesterase on frozen sections, which is sufficient to diagnose the classical disease in rectal mucosal biopsies. In ultrashort Hirschsprung's disease, increased acetylcholinesterase activity is demonstrable only in nerve fibres of the muscularis mucosae and submucosa, but not the lamina propria mucosae. Submucosal and myenteric ganglia are physiologically scarce in the most distal rectum; absence of ganglia in a biopsy of the rectoanal transition must not be (wrongly) interpreted as ultrashort Hirschsprung's disease. Therefore, a diagnosis of ultrashort Hirschsprung's disease can be made exclusively using an enzyme histochemical reaction for acetylcholinesterase.     

Acetylthiocholinesterase staining activity of rectal mucosa. Its use in the diagnosis of Hirschsprung's disease

Increased acetylthiocholinesterase (AchE) reactivity in the rectal lamina propria and lamina muscularis mucosae was used to diagnose Hirschsprung's disease. We processed 131 specimens with the AchE reaction; 43 were suction biopsy specimens and the rest were full-thickness specimens. Of the 68 specimens in which neurocytes were present, none demonstrated a diffuse increase in the number of nerve fibers. However, 15 showed focal increases in the numbers of fibers that were not large enough to be regarded as indicative of Hirschsprung's disease. All patients with a diffuse increase in nerve fibers, regardless of the type of biopsy, were shown to have Hirschsprung's disease. The AchE staining reaction did, however, produce a 29% rate of false-negative reactions (16 of 56 specimens) in patients with Hirschsprung's disease. These data demonstrate that an abnormal pattern of AchE reaction is diagnostic of aganglionic megacolon, whereas a normal pattern does not exclude the disease.     

Acetylcholinesterase histochemistry of rectal suction biopsies in the diagnosis of Hirschsprung's disease.

Rectal suction biopsy with acetylcholinesterase (AChE) histochemistry has gained increased acceptance as the means of definitely diagnosing Hirschsprung's disease (HD) as well as of excluding this diagnosis when evaluating children with low intestinal obstruction or chronic constipation since the report of Meier-Ruge et al. in 1972. But this AChE histochemical study has not been reported yet in Korea. During the 14-month period from April, 1991 through June, 1992, 37 children, aged 3 days to 17 years had rectal suction biopsies for the diagnosis or exclusion of HD. In this study, AChE histochemistry (N = 37) was compared with hematoxylin & eosin (H&E) staining of same suction biopsy specimens (N = 35) for diagnostic accuracy. The histochemical criterion used for the diagnosis of Hirschsprung's disease was that of Chow et al. (1977), i.e., the presence of many coarse discrete cholinergic fibers in the muscularis mucosae and in the immediately subjacent submucosa regardless of an infiltration of cholinergic fibers in the lamina propria. Of 13 biopsies from the patients with Hirschsprung's disease (N = 13), there were 12 positive reactions, and one false negative reaction in a neonate with total colonic aganglionosis. All biopsies from 24 unaffected children demonstrated negative reactions with no false positive reaction. In comparison, of the 35 specimens examined by H&E staining, ganglion cells were present in the submucosal Meissner's plexus only in 15 of these 24 unaffected children. In conclusion, a 97% diagnostic accuracy was achieved with AChE histochemistry compared with a 74% accuracy with H&E staining (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Hirschsprung's disease: an appraisal of histochemically demonstrated acetylcholinesterase activity in suction rectal biopsy specimens as an aid to diagnosis

Suction rectal biopsy specimens, from a series of 168 infants and children with constipation and other gastrointestinal problems, were stained with a sensitive acetylcholinesterase method, and the results were compared with routine histology, radiology, anorectal manometry, and the final diagnosis. In all cases of Hirschsprung's disease, there was an increase in numbers and sizes of cholinergic nerves in the lamina propria and muscularis mucosae. No false-positive or false-negative results were found. The test was found to be more reliable and consistent than other methods available.     

Hirschsprung's disease: practical considerations

Hirschsprung's disease (1/5000 live births) is defined by the congenital absence of neuronal cells in the nervous plexuses in the distal part of the digestive tract. The disease affects the rectum and sigmoid colon in 80% of cases, or is more extensive. Hirschsprung's disease is suspected in cases of low gastrointestinal obstruction in the neonatal period, or in cases of chronic severe constipation in childhood. It is diagnosed by pathological examination of rectal biopsies that include the submucosa. After standard staining, multiple sections are scrutinized for neuronal cells. Acetylcholinesterase staining is performed on a frozen fragment to demonstrate the hyperplasia of cholinergic fibers that is very suggestive of Hirschsprung's disease. This hyperplasia decreases from the rectum to the splenic flexure of the colon. Hyperplasia of extrinsic nerve fibers and rarefaction of neuromuscular junctions in Hirschsprung's disease may be demonstrated immunohistochemically. Differential diagnosis includes chronic intestinal pseudo-obstructions. The treatment for Hirschsprung's disease is, most often, anastomosis of the normally innervated gut to the anal canal. Peri- or pre-operative biopsies assist surgery, but their interpretation is difficult in the transitional zone. The examination of the surgical specimen allows measurement of the aganglionic segment and transitional zone. Different genes (RET, most often) may be involved in sporadic or familial Hirschsprung's disease. Hirschsprung's disease is associated with other digestive or extra-digestive abnormalities in 5 to 30% of patients. Associated abnormalities may delay the diagnosis and treatment of Hirschsprung's disease.     

Evaluation of PGP9.5 in the diagnosis of Hirschsprung's disease.

The ability of an acetylcholinesterase-stained frozen section to detect an increase in large cholinergic nerve fibres within the muscularis mucosae and extending into the lamina propria was a significant step forward in the diagnosis of Hirschsprung's disease (HD). However, such frozen section diagnosis is not always possible. The purpose of this study was to assess the ability of PGP9.5 to detect this pattern of mucosal nerve fibre staining immunohistochemically. Sixty-four specimens were included in the study. Twenty-six of these had been diagnosed as HD by conventional means. All cases were stained immunohistochemically with PGP9.5, S100, and anti-neurofilaments (NF). Twenty-four cases of HD were also stained with neurone-specific enolase (NSE). PGP9.5 reliably stained fibres in the mucosal and submucosal plexuses, and ganglion cells, when the latter were present. This positive staining of ganglion cells was more intense than that seen with NSE, and the positive fibre staining was more intense than that seen with NF. Increased lamina propria fibres were detected with PGP9.5 in only 37 per cent of HD cases compared with S100 positive staining in 60 per cent of cases. However, when S100 staining was assessed alone, it gave a higher false-negative rate in diagnosing HD than PGP9.5 used alone. Therefore we would recommend the use of PGP9.5 and S100 together for the immunohistochemical diagnosis of HD in formalin-fixed biopsies.     

Immunoperoxidase stains of ganglion cells and abnormal mucosal nerve proliferations in Hirschsprung's disease

Hirschsprung's disease is congenital aganglionosis of the distal colon. The affected bowel shows an abnormal proliferation of mucosal nerve fibers by acetylcholinesterase stains. We retrospectively reviewed biopsy specimens from patients with suspected and proven Hirschsprung's disease, performed immunoperoxidase stains for S-100 protein and neuron-specific enolase (NSE), and compared these results to routine histologic findings and acetylcholinesterase stains. Ganglion cells were demonstrated by immunoperoxidase in 63 of 69 specimens containing ganglion cells and in 1 specimen interpreted as aganglionic by hematoxylin-eosin staining. Increased numbers of nerve fibers in the muscularis mucosae and deep lamina propria by S-100 staining were detected in 8 of 8 specimens diagnostic for Hirschsprung's disease by hematoxylin-eosin and acetylcholinesterase stains and in 1 specimen diagnostic for colonic neuronal dysplasia (a disorder related to Hirschsprung's disease). Whereas 45 of 67 specimens from unaffected bowel showed a normal number and distribution of nerve fibers by S-100 staining, in 22 the pattern resembled that of Hirschsprung's disease. Specimens from affected colon also showed hypertrophied submucosal nerve trunks by S-100 stain (average nerve trunk thickness, 29.8 micron in affected bowel, 16.1 micron in unaffected segments--p less than 0.03). We conclude that NSE and S-100 stains are of value in demonstrating ganglion cells in suspected cases of Hirschsprung's disease and colonic neuronal dysplasia. The acetylcholinesterase stain is preferred over S-100 stain for detecting mucosal nerve proliferations in affected bowel. Submucosal nerve trunk thickness, although significantly different in affected and unaffected colon, is not of diagnostic value because of the wide variation in the measurements in the two groups.     

Rectal mucosal biopsy in aganglionosis and allied conditions

Rectal mucosal biopsies were performed in 146 patients suspected of having Hirschsprung's disease. The biopsies were serially sectioned and screened for the presence of ganglion cells. In the 101 cases in which ganglion cells were found, the diagnosis of Hirschsprung's disease was ruled out. In 45 patients, histologic examination revealed the typical features of Hirschsprung's disease, i.e., the absence of ganglion cells and the presence of numerous hypertrophied nerve bundles. The varied morphologic features of Meissner's plexus in patients of different ages and the diagnostic pitfalls are described in detail. Serial frozen sections stained with hematoxylin-eosin were examined in eight cases of neonatal intestinal obstruction and enterocolitis. This method was found to be useful and reliable in emergencies. In three of these cases ganglion cells were found and major surgical procedures were avoided. In 73 cases, staining for acetylcholinesterase activity was performed. The results matched the microscopic findings in all but three false-positive cases.     

Pathology of chronic constipation in pediatric and adult coloproctology.

In colonic motility disorders, a pathohistological diagnosis based solely on formalin-fixed gut is often inconclusive. Classical histological techniques or immunohistochemistry represent a static staining. In contrast, native tissue submitted to enzyme histochemistry provides functional information about the effectiveness of the cellular performance. Routinely, a complementary set of reactions is performed and includes acetylcholinesterase (AChE), lactic and succinic dehydrogenase, as well as nitroxide synthase reactions. In this monograph, the whole spectrum of different anomalies of the colonic wall is illustrated in a systematic fashion: Hirschsprung's disease is characterized by an increase in AChE activity of parasympathetic nerve fibers of the rectosigmoid. In ultrashort Hirschsprung's disease, only enzyme histochemistry renders a reliable diagnosis possible in biopsies of the anal ring. Aganglionosis of the musculus corrugator cutis ani shows a localized increase of AChE activity in nerve fibers, similar to Hirschsprung's disease, not detectable in conventional histology. Immaturity, hypoganglionosis and neuronal dysganglionosis can be clearly recognized in dehydrogenase reactions. Enzyme histochemical reactions are complemented by picrosirius red staining for assessment of the collagen texture of the muscularis propria. Absence or intertenial interruption of the continuous connective tissue layer between circular and longitudinal muscle of the muscularis propria has been termed aplastic or atrophic desmosis, respectively. Many of the entities described are also observed in adults. Atrophic hypoganglionosis or atrophic desmosis with loss of the myenteric plexus connective tissue fascia is implied as a frequent cause of chronic constipation in adults. The essential contribution of a functional histopathological technique towards a reliable diagnosis of gut dysfunction in native tissue is extensively demonstrated in great detail in more than two hundred figures.     

Distribution of plasma cells in normal rectal mucosa

In a survey of 36 histologically normal rectal biopsies, plasma cell counts were recorded at different depths of the lamina propria. The necessity of surveying the lamina propria at every level from the muscularis mucosae to the epithelium, in order to obtain an accurate estimate of plasma cell frequency is demonstrated. The relative accuracy of counting smaller areas of lamina propria is tested and the ratio of epithelium to lamina propria area established.     

Muscularis mucosae versus muscularis propria in gallbladder, cystic duct, and common bile duct: smoothelin and desmin immunohistochemical study

The muscle layer in the cystic duct and common bile duct is not well defined, and it is unresolved whether it represents muscularis mucosae or muscularis propria. Smoothelin is a novel smooth muscle–specific contractile protein expressed only in fully differentiated smooth muscle cells of the muscularis propria and not in proliferative or noncontractile smooth muscle cells of the muscularis mucosae. In this study, we characterize the histologic aspects of the muscle layer in gallbladder, cystic duct, and common bile duct by evaluation of routine histologic sections and the utilization of immunohistochemistry using desmin and smoothelin. Formalin-fixed, paraffin-embedded sections of the gallbladder (15 cases), cystic duct (11 cases), and common bile duct (10 cases) were stained for smoothelin and desmin. Staining intensity was evaluated as weak or strong. The staining pattern score was evaluated as follows: 0 or negative = less than or equal to 5% positivity, +1 or focal = 6% to 10% positivity, +2 or moderate = 11% to 50% positivity, and +3 = greater than 50% muscle cells positivity. With desmin, strong and diffuse (+3) staining was observed in all gallbladder cases (15/15, 100%), highlighting one continuous muscle layer. The muscle layer was discontinuous and interrupted in all cystic duct cases and in most common bile ducts, highlighted by the desmin stain. Smoothelin intensely stained (at least +2) muscle fibers in the gallbladder in 11 (73%) of 15 cases similar to that observed with desmin staining. In contrast, common bile ducts predominantly had absent or weak and focal immunostaining (0 or +1 staining) with smoothelin (7/10, 70%), with only a few cases (3/10, 30%) having +2 staining (no cases with +3). Cystic ducts also showed absent or weak and focal immunostaining with smoothelin, with 5 (44%) of 11 cases showing 2+ immunostaining with smoothelin (no cases with 3+). Based on our findings, we conclude that, in the gallbladder wall, the muscle layer is muscularis propria and there is no muscularis mucosae present. In the cystic duct and common bile duct, only an attenuated and incomplete muscle layer of muscularis mucosae is present; because there is no muscularis propria, there probably is limited contractile function. Differentiating these anatomical muscle structures may be important for the pathologic staging of carcinoma in these organs.     

An immunohistochemical study of the enteric neural plexi in Hirschsprung''s disease

The diagnosis of Hirschsprung's disease relies upon histology and acetylcholinesterase histochemistry of the enteric neural plexi. A distinctive neurofilament protein staining pattern has been claimed in Hirschsprung's disease. We studied 10 colons affected by Hirschsprung's disease, together with appropriate controls using antibodies to neurofilament protein (NFP; monoclonal), neurone-specific enolase (NSE), glial fibrillary acidic protein (GFAP) and S-100 protein (all polyclonal), and conventional histology and histochemistry, seeking an immunohistochemical diagnostic method. We found staining for NFP, NSE and S-100 protein of many of the nerve fibres and satellite cells in the enteric plexi, but without significant differences between affected and unaffected colons. Staining for GFAP was weakly positive in a minority of cases and controls and the majority of neurones in control sections stained for NSE. In contrast to acetylcholinesterase little staining was localized in the lamina propria. Staining for NSE and S-100 is useful in identifying immature ganglion cells in paediatric large intestine.     

Solitary ulcer syndrome of the rectum--a histopathologic characterisation of 33 biopsies

Histological analysis of 33 rectal biopsies from 26 patients of solitary ulcer syndrome (SUS) of rectum was undertaken. Fibrous obliteration and smooth muscle extension into the lamina propria were the characteristic and most constant findings. The limitation of the biopsy procedure in procuring deeper tissue made the detection of colitis cystica profunda rare in our study. A combination of fibrosis of the lamina propria, superficial mucosal ulceration, muscularis mucosae hypertrophy and submucosal fibrosis, along with the clinical suspicion should clinch the diagnosis of SUS.     

Autoimmune enteric leiomyositis: a rare cause of chronic intestinal pseudo-obstruction with specific morphological features

Autoimmune enteric leiomyositis is an extraordinary rare cause of acquired chronic intestinal pseudo-obstruction in children. We report a 5-year-old girl who developed chronic intestinal pseudo-obstruction 3 years after an autoimmune hepatitis. Mucosal biopsies of the upper gastrointestinal tract and colon showed minimal inflammatory changes. On full-thickness biopsies of the small intestine, a dense lymphocytic infiltrate of the muscularis propria was seen, mainly consisting of cytotoxic T lymphocytes. Smooth muscle fibers were degenerated and diminished, but the myenteric plexus was intact. The coexistence of an autoimmune hepatitis in our case indicates an expansion of autoreactive T cells to homologous self-antigens. It is of practical importance for histopathological diagnosis that inflammation in autoimmune enteric leiomyositis affects the muscularis propria of the small intestine, whereas mucosa and submucosa do not show severe inflammatory changes. Therefore, correct diagnosis may be missed in peroral and peranal mucosal biopsies, but full-thickness biopsies are required.     

The formation of the chick ileal muscle layers as revealed by α-smooth muscle actin immunohistochemistry

The genesis of intestinal smooth muscle layers was immunohistochemically investigated by use of an antibody to α-smooth muscle actin (α-SMA) in the developing chick ileum. Myoblast cells positive for α-SMA were already found in the presumptive circular muscle layer on E 8.5. On E 11.5 radially oriented muscle fibers were protruded from the outermost layer of the developing circular musculature and then formed a tuft-like aggregates. These radial muscle bundles were bent into an L-shape. The long distal extension of muscle bundles run parallel to the long axis of the ileal loop and developed into the longitudinal muscle layer. The obliquely oriented muscle fibers, locating at the intermuscular space of the muscularis propria, probably are to be considered a remnant of the short extension of radial muscle bundles. The muscularis mucosae was formed by the processes equivalent to the genesis of longitudinal muscle layer. On E 14.5 centripetally oriented muscle fibers emerged from the innermost layer of circular musculature. The long distal extension of centripetal fibers lay along the inner surface of developing circular musculature. On E 19.5 the longitudinal muscle layer of the muscularis mucosae was newly formed by separating from the circular musculature. The villous myoblast cells initially developed from the innermost layer of the muscularis mucosae on E 18.5, and were widely distributed in the lamina propria mucosae on E 20.5. Temporal and chronological pattern in expression of α-SMA was observed during the development of the chick intestinal smooth muscle. By E 14.5 the entire layer of the muscularis propria was intensely immunostained for α-SMA, but from E 15.5 onward the staining intensity gradually began to decrease from the outer half of the circular musculature. Finally, the immunoreactivity was localized in the inner layer of circular muscle and the longitudinal muscle layer. A possible functional role of this inner layer of circular muscle is discussed.     

Limited smoothelin expression within the muscularis mucosae: validation in bladder diverticula

Smoothelin, a marker of differentiated smooth muscle, is diffusely expressed by bladder muscularis propria and is negative to only weakly and focally expressed in muscularis mucosae. We used bladder diverticula, which lack muscularis propria and frequently demonstrate hyperplastic muscularis mucosae, to evaluate the use of smoothelin immunoreactivity in diagnostic pathology. Diverticula from 40 patients (21 with benign features, 19 with neoplastic features) were studied. Immunohistochemistry was performed using smoothelin antibody (clone R4A, 1:150 dilution; Abcam, Cambridge, MA); and tissue was scored as 0 (no expression), 1+ (moderate expression b10% of cells), 2+ expression (moderate expression N10% of cells), and 3+ (robust diffuse expression). All diverticula contained muscularis mucosae of varying caliber; staining in diverticular muscularis mucosae was compared with historic results in the muscularis mucosae of cystectomy specimens. Hyperplastic muscularis mucosae occurred in 31 (78%) of 40 cases. Smoothelin immunoreactivity in the diverticular muscularis mucosae included 0 (16/40, or 40%); 1+ (11/40, or 27.5%); 2+ (13/40, or 32.5%); and 3+ (0/40, or 0%), with a slightly higher 2+ expression level in hyperplastic versus nonhyperplastic muscularis mucosae (35% versus 22%). Adjacent normal muscularis propria, present in 12 specimens, demonstrated 3+ muscularis propria immunoreactivity. Comparison between diverticula with benign and neoplastic features showed no significant difference in smoothelin immunoreactivity. No correlation was evident with smoothelin immunohistochemistry and muscle caliber. Smoothelin immunoreactivity in bladder diverticula confirms the limited nature of smoothelin expression in the muscularis mucosae and represents a useful ancillary technique in the proper histopathologic evaluation of diverticular and nondiverticular bladder carcinomas. A strong and robust staining of smooth, rounded muscle with smoothelin remains a useful diagnostic adjunct in the reliable recognition of muscularis propria.     

Neuronal hypertrophy in acute appendicitis

OBJECTIVE: The pathogenesis of appendicitis remains poorly understood. However, there is increasing evidence of involvement of the enteric nervous system in immune regulation and in inflammatory responses. This study was set up to characterize the status of the enteric nervous system in normal and in inflamed appendixes. METHODS: S100- and 2',2'-cyclic nucleotide 3' phosphodiesterase-positive Schwann cells, synaptophysin, and neuron-specific, enolase-positive nerve fibers and tryptase-positive mast cells were evaluated with immunohistochemical staining in surgically resected appendixes from 20 children with histologically proven acute appendicitis (HA), 10 histologically normal appendixes (HN) from patients with a clinical diagnosis of appendicitis, and 10 normal appendixes from patients undergoing elective abdominal surgery. Immunostained sections were subjected to quantitative image analysis. The number and size of ganglia and the number of nerve fibers, Schwann cells, and mast cells in each tissue compartment was quantitatively or semiquantitatively measured. RESULTS: Increased numbers of fibers, Schwann cells, and enlarged ganglia, widely distributed in the muscularis externa and submucosa, were seen in all HA appendixes and in 4 of 10 HN appendixes. The number and size of ganglia in muscularis externa and in the submucosa of appendixes with HA were significantly greater compared with those in control appendixes (P <.001). A significantly increased number of individually stained nerve fibers and Schwann cells (P <.05) were present in the muscularis externa in HA appendixes compared with control appendixes. Significantly increased numbers of tryptase-positive mast cells (P <.05) were present in the submucosa, muscularis, and especially in the lamina propria in HA specimens, compared with that of control tissue. CONCLUSIONS: The significant increase in neural components and mast cells in acute appendicitis is unlikely to develop during a single acute inflammatory episode. This suggests an underlying chronic abnormality as a secondary reaction to repeated bouts of inflammation, obstruction, or both. These results challenge our current understanding of the pathophysiological processes that give rise to acute appendicitis.     

The formation of the chick ileal muscle layers as revealed by alpha-smooth muscle actin immunohistochemistry

The genesis of intestinal smooth muscle layers was immunohistochemically investigated by use of an antibody to α-smooth muscle actin (α-SMA) in the developing chick ileum. Myoblast cells positive for α-SMA were already found in the presumptive circular muscle layer on E 8.5. On E 11.5 radially oriented muscle fibers were protruded from the outermost layer of the developing circular musculature and then formed a tuft-like aggregates. These radial muscle bundles were bent into an L-shape. The long distal extension of muscle bundles run parallel to the long axis of the ileal loop and developed into the longitudinal muscle layer. The obliquely oriented muscle fibers, locating at the intermuscular space of the muscularis propria, probably are to be considered a remnant of the short extension of radial muscle bundles. The muscularis mucosae was formed by the processes equivalent to the genesis of longitudinal muscle layer. On E 14.5 centripetally oriented muscle fibers emerged from the innermost layer of circular musculature. The long distal extension of centripetal fibers lay along the inner surface of developing circular musculature. On E 19.5 the longitudinal muscle layer of the muscularis mucosae was newly formed by separating from the circular musculature. The villous myoblast cells initially developed from the innermost layer of the muscularis mucosae on E 18.5, and were widely distributed in the lamina propria mucosae on E 20.5. Temporal and chronological pattern in expression of α-SMA was observed during the development of the chick intestinal smooth muscle. By E 14.5 the entire layer of the muscularis propria was intensely immunostained for α-SMA, but from E 15.5 onward the staining intensity gradually began to decrease from the outer half of the circular musculature. Finally, the immunoreactivity was localized in the inner layer of circular muscle and the longitudinal muscle layer. A possible functional role of this inner layer of circular muscle is discussed. Accepted: 16 July 1999     

Gastrointestinal amyloid deposition in AL (primary or myeloma-associated) and AA (secondary) amyloidosis: Diagnostic value of gastric biopsy

Gastrointestinal amyloid deposition was investigated in 21 autopsy cases of nonhereditary systemic amyloidosis, 18 of the AL (primary or myeloma-associated) type and three of the AA (secondary) type. Vascular deposition of amyloid, most apparent in the submucosa, was found in all cases. Parenchymal deposition was observed mainly in the muscularis mucosae and muscularis externa in the AL type, and in the lamina propria mucosae in the AA type. Comparison of amyloid deposition in the stomach and rectum revealed no differences for the AA type. In the AL type, however, deposition in the lamina propria mucosae and muscularis mucosae was more frequent and marked in the wall of the stomach than in the rectum. Thus, gastric biopsy would be more valuable than rectal biopsy in the diagnosis of AL amyloidosis.     

Acetylcholinesterase-activity in rectal mucosa of children with obstipation

Summary The results are presented of a clinical-enzyme histochemical evaluation of the activity of acetylcholinesterase in the rectal mucosa of 46 children with obstipation. In four cases abundant and coarse acetylcholinesterase positive nerve fibres were present in the lamina propria of the mucosa. Only in these 4 cases was the diagnosis of Hirschsprung's disease supported by the clinical course.Local accumulations of fine acetylcholinesterase positive nerve fibres or accumulations of acetylcholinesterase positive foamy or structureless material were not correlated with Hirschsprung's disease.