•
•
Radiographic Features of Colitis Associated with the Hemolytic-Uremic Syndrome 1
Pediatric Radiology
Richard B. Peterson, M.D., William P. Meseroll, M.D., Gary G. Shrago, M.D., and Charles A. Gooding, M.D. Four cases of colitis associated with the prodromal phase of the hemolytic-uremic syndrome are presented. Abnormalities demonstrable on barium enema examination consist of prominent filling defects, marginal serrations, and mucosal edema. Segmental bowel dilatation and areas of stenosis may also be present. Although nonspecific in itself, this appearance of the colon when correlated with the clinical history and peripheral blood smear should enable the radiologist to suggest the diagnosis of hemolytic-uremic syndrome. INDEX TERMS: Colitis. Gastrointestinal tract, abnormalities. Gastrointestinal tract, mucosa • Hemolytic-Uremic Syndrome
Radiology 118:667-671, March 1976
•
•
syndrome (HUS) is a distinct clinical and pathological entity (11) of variable severity and undefined etiology characterized by hemolytic anemia, acute renal disease, and, usually, thrombocytopenia. Initially described in 1955 by Gasser et al. (5), this illness usually occurs in infants and young children. A prodrome of gastroenteritis with bloody diarrhea commonly precedes the more striking hematologic and renal
manifestations of the disease by several days to several weeks (10). Few examples (1) of the radiographic manifestations on barium enema examination of the colitis associated with the prodromal phase of this syndrome have been described. We wish to present the case histories and barium enema studies of 4' patients with HUS and to discuss the appearance of this associated colitis.
T
HE HEMOLYTIC-UREMIC
Fig. 1. CASE I. A. This filled barium enema study shows prominent filling defects in the cecum and ascending colon which represent "transverse ridging," probably due to colonic spasm. Marginal irregularities of the descending colon are also present. B. A spot film of the descending colon shows marginal serrations representing multiple superficial ulcerations. 1 From the Departments of Radiology, letterman Army Medical Center (R. B. P., G. G. S.), and the University of California School of Medicine (W. P. M., C. A. G.), San Francisco, Calif. Accepted for publication in September 1975. The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense. elk
667
668
RICHARD
B.
PETERSON AND OTHERS
March 1976
men with some degree of rebound but no palpable masses. Initial laboratory findings showed a hemoglobin value of 15.8 g/100 ml, hematocrit of 46%, and a white blood cell count of 23,000/mm 3 . The blood urea nitrogen was 14 mg/100 ml. A barium enema study (Fig. 2) performed on the day of admission was read as being consistent with acute ulcerative colitis. A proctoscopic examination showed granular mucosa and blood coming from above 10 cm. The patient was treated with intravenous fluids but without remission of her abdominal symptoms. On the second hospital day there was a reduction in her urine output. Two days later she became acutely distressed. She was confused and agitated, and pallor of the skin was noted. She vomited coffee-ground-Iike material. The laboratory findings showed a hemoglobin value of 9.6 g/100 ml, hematocrit of 26 %, and a white blood cell count of 41,300/mm3 . The platelet count was 40,000/mm3 . A peripheral blood smear showed schistocytes and burr cells. On the same day, the patient became anuric and required peritoneal dialysis and, later, hemodialysis. The anuric state persisted for nearly a month, followed by gradually increasing urine output. On the 45th hospital day, repeat proctoscopic and barium enema examinations were normal. An upper gastrointestinal series was also normal. On the 62d hospital day the patient was discharged with a hemodialysis regimen.
Fig. 2. CASE II. Barium study reveals narrowing of the colon lumen and marginal irregularities of the ascending and transverse colon. Asymmetric marginal indentations of the descending colon are characteristic of "thumbprinting."
CASE REPORTS CASE I (V. S.): This 10-year-old black boy was admitted because of abdominal pain, diarrhea, and vomiting of three days duration. Traces of dark red blood were noted in the numerous watery stools. Physical examination showed mild dehydration and abdominal tenderness with a mild degree of rebound. Laboratory findings on admission included a hematocrit of 45 %, a blood urea nitrogen of 30 mg/100 ml and a white blood cell count of 20,800/mm3 . Urinalysis showed 2+ proteinuria and excretory urogram was normal. Figure 1 shows the colon after a barium enema. Following treatment with intravenous fluids, the diarrhea gradually became less frequent. On the fourth hospital day, proctoscopic examination revealed mucosal inflammation and friability which was felt to be representative of ulcerative colitis. The same day the hematocrit fell to 22% with a hemoglobin value of 8.1 g/ 100 ml and two units of whole blood was given. There was thrombocytopenia of 12,000/mm3 . Urinary sediment contained 3+ protein, red cells, white cells, and casts. Shortly thereafter, peak levels of blood urea nitrogen of 64 mg/100 ml and serum creatinine of 2.6 mg/100 ml were obtained. The peripheral blood smear showed abnormal red-cell morphology, including burr cells and schistocytes. Coombs' test was negative. Urine output remained adequate throughout hospitalization. Diagnosis of HUS was made on the fifth hospital day. By the eighth hospital day, all chemical parameters started improving and continued to do so until discharge on the 18th day. A proctoscopic examination following discharge showed nonfriable mucosa, and a rectal biopsy was normal. CASE II (C. L.): This 10-year-old girl was admitted because of a three-day history of diarrhea, fever, and abdominal pain with recent onset of severe repeated bloody diarrhea and vomiting. Physical examination showed some cutaneous dehydration and a tender abdo-
CASE III (S. C.): This 2Y2-year-old white boy was admitted because of diarrhea and vomiting during the previous four days. Many of the stools contained bright red blood. Three weeks before, the child had had an upper respiratory illness which responded to ampicillin. Physical examination on the day of admission revealed that the child was lethargic and pale with mild dehydration and slight distension of the abdomen with minimal tenderness. The initial laboratory findings included a hemoglobin of 13.7 g/100 ml, a white blood cell count of 25,600/mm3 , a blood urea nitrogen of 10 mg/100 ml, and a serum creatinine of 0.6 mg/100 ml. The child was thought to have gastroenteritis secondary to a viral illness and was given intravenous fluids for dehydration. On the third hospital day there had been no improvement and the child appeared pale. The laboratory findings showed a hemoglobin value of 6.7 g/ 100 ml. The blood urea nitrogen had increased to 31 mg/ 100 ml and the serum creatinine had increased to 1.5 mgt 100 ml. The peripheral blood smear showed many fragmented cells and helmet cells. Coombs' test was negative. A barium enema study (Fig. 3) showed prominent marginal irregularities of the colon. The blood urea nitrogen and serum creatinine levels continued to climb until the seventh hospital day, when peak concentrations of 181 mg/100 ml and 5.9 mg/100 ml were obtained. Oliguria developed and persisted over several days. The child did not become anuric. Following treatment with several packed-cell transfusions and careful fluid management, a gradual improvement in both the child's clinical picture and laboratory findings was observed and he was discharged on the 20th hospital day. CASE IV (D. K.): This 5-year-old white boy exhibited nonproductive cough, fever to 39.5°C, and one episode of vomiting seven days prior to admission. These symptoms persisted and the patient was treated with penicillin. Shortly thereafter, frequent diarrheal episodes with blood streaking began. The child became pale and listless and he was admitted for treatment of dehydration. A barium enema study (Fig. 4, A) was read as being compatible with ulcerative colitis and the child was initially treated accordingly. During the hospitalization his hematocrit dropped and he required transfusions. Proteinuria and hematuria developed. Peak levels of blood urea nitrogen of 96 mg/100 ml and serum creatinine of 4.0 mg/ 100 ml were obtained; however, he continued to maintain an adequate urine output. Mild peripheral edema developed. His platelet count fell to 40,000/mm3 , and burr cells and schistocytes were seen on the peripheral blood smear. Sigmoidoscopy was performed and showed a gross area of superficial ulceration. A rectal biopsy re-
Pediatric Radiology
Fig. 3. CASE III. A. This spot film of the filled colon shows prominent "thumbprints" in the area of the splenic flexure. B. Postevacuation barium enema radiograph shows grossly abnormal colonic mucosa. There is a dilated segment of small bowel with marginal irregularity (arrows) suggesting mucosal edema.
Fig. 4. CASE IV. A. This barium enema study shows marginal irregularities and narrowing of segments Of the aescending colon. Thickened mucosal folds in the transverse colon represent edema. B. Two weeks later, a repeat barium study demonstrates a relatively normal mucosal pattern. The area of persistent narrowing in the descending colon (arrow) represents stricture formation.
669
670
RICHARD B. PETERSON AND OTHERS
vealed nothing unusual. Subsequent to the diagnosis of HUS he gradually showed improvement on a restricted fluid regimen. On the 18th hospital day a repeat barium enema study (Fig. 4, B) showed marked improvement of the colon and the patient was discharged on the 22d hospital day.
DISCUSSION HUS has been recognized with ever-increasing frequency since its initial description (7, 13). The clinical entity most similar to HUS is childhood thrombotic thrombocytopenic purpura (11). The distinction between the two may be slight and represent only a difference in the distribution of the vascular lesions (3). HUS has a wide spectrum of severity ranging from asymptomatic cases (18) to death, usually from renal failure (7). The pathogenetic mechanism is generally thought to be an intravascular coagulation of unknown etiology (4) manifested by fibrin deposition in the microvasculature of the kidneys and other organs (7). The anemia of HUS occurs as a result of this microangiopathy, with the peripheral blood smear showing characteristic morphological abnormalities of the red cells (3). Typically, the disease begins in a previously healthy child who contracts gastroenteritis or, less commonly, an upper respiratory illness (10) as the initial recognized event. The gastrointestinal stage of the disease frequently resembles that seen with many viral diseases (6), and definitive treatment may be delayed because of an erroneous diagnosis. In some cases the severe bloody diarrhea and clinical presentation may mimic ulcerative colitis (2). Diagnosis is obvious once the hematologic and renal abnormalities occur but is difficult during the prodromal aspects of the disease. The course of the syndrome is variable and prognosis is related to the severity of renal involvement (7, 10). Therapy is directed toward management of the acute renal failure and correction of the hematologic abnormalities (8). The value of anticoagulant and fibrinolytic therapy in HUS is controversial (3, 7, 8, 17); however, some authors feel that administration of heparin in the early stages of the disease may be of benefit (4, 9). Unfortunately, the diagnosis is seldom, if ever, made at that time. All of the patients presented in this paper showed prominent filling defects on the barium studies, represented by "thumbprinting," "pseudotumors," and "transverse ridging." The "thumbprint" or "pseudotumor" pattern has been shown to represent submucosal hemorrhage due to vascular occlusion in the wall of the colon (14). Bar-Ziv et el. (1) suggest that this appearance may represent the early expression of the intravascular clotting which is later manifested by anemia and thrombocytopenia. "Transverse ridging" may be a manifestation of spasm (15). Both the marginal serrations which represent small ulcerations and the mucosal edema pattern seen on the barium studies are nonspecific in nature but can be found in ischemic disease of the bowel (12, 14). Bowel distension is a reflection of
March 1976
vascular compromise to the muscular layer of the gastrointestinal tract (16). With incomplete healing of the bowel wall, fibrotic changes causing stricture and stenosis will occur (15, 19). All of these radiographic manifestations reflect the underlying pathological process of ischemia, presumably due to occlusion of the intestinal microvasculature by fibrin deposits similar to those found in the kidneys. On the repeat barium enema examination shown in CASE IV (Fig. 4, B), there is resolution of all the radiographic abnormalities except the stenosis, indicating the potential reversible nature of these lesions. The radiographic findings presented above may simulate inflammatory colon diseases such as acute ulcerative or granulomatous colitis, pseudomembranous colitis, shigellosis, or salmonellosis. Although nonspecific in itself, the radiographic appearance of the colon when correlated with the clinical history and peripheral blood smear should suggest the likelihood of HUS. A most important aspect of the therapy of HUS is prompt recognition of the disease (13); the radiologist may be the first to suspect this syndrome before the severe hematologic and renal abnormalities occur. ACKNOWLEDGMENT: We wish to thank Donald R. Kirks, M.D., of Oakland, California, for supplying the roentgenograms for CASE III.
REFERENCES 1. Bar-Ziv J, Ayoub JIG, Fletcher BD: Hemolytic uremic syndrome: a case presenting with acute colitis. Pediatr Radiol 2:203205,Oct 1974 2. Berman W Jr: The hemolytic-uremic syndrome: initial clinical presentation mimicking ulcerative colitis. J Pediatr 81:275-278, Aug 1972 3. Brain MC: The haemolytic-uraemic syndrome. Semin HematoI6:162-180, Apr 1969 4. Brain MC: Microangiopathic hemolytic anemia. Ann Rev Med 21:133-144, Feb 1970 5. Gasser C, Gautier E, Steck A, et al: Harnolytlsch-urarnische Syndrome: bilaterale Nierenrindennekrosen bei akuten erworbenen harnolytischen Anarnlen. Schweiz Med Wochenschr 85: 905-909,20 Sep 1955 6. Gianantonio CA, Vitacco M, Mendilaharzu F, et al: The hemolytic-uremicsyndrome. J Pediatr 64:478-491, Apr 1964 7. Gianantonio CA, Vitacco M, Mendilaharzu F, et al: The hemolytic-uremic syndrome. Renal status of 76 patients at longterm follow-up. J Pediatr 72:757-765,Jun 1968 8 Gilchrist GS, Lieberman E, EkertH, et al: Heparin therapy in the haemolytic-uraemic syndrome. Lancet 1:1123-1126, Jun 1969 9. Katz J, Krawitz S, Sacks PV, et al: Platelet, erythrocyte, and fibrinogen kinetics in the hemolytic-uremic syndrome of infancy. J Pediatr 83:739-748, Nov 1973 10. Lieberman E: Hemolytic-uremic syndrome. J Pediatr 80: 1-16, Jan 1972 11. Lieberman E, Heuser E, Donnell GN, et al: Hemolytic-uremic syndrome. Clinical and pathological considerations. N Engl J Med 275:227-236, 4 Aug 1966 12. Margulis AR: Radiology of ulcerating colitis. Radiology 105:251-263, Nov 1972 13. PieI CF, Phibbs RH: The hemolytic-uremic syndrome. PediatrClin North Am 13:295-314, May 1966 14. Schwartz S, Boley S, Lash J, et al: Roentgenologic aspects of reversible vascular occlusion of the colon and its relationship to ulcerative colitis. Radiology 80:625-635, Apr 1963
Vol. 118
RADIOGRAPHIC FEATURES OF COLITIS
15. Schwartz S, Boley SJ, Robinson K, et al: Roentgenologic features of vascular disorders of the intestines. Radiol Clin North Am 2:71-87, Apr 1964 16. Shapeero LG, Myers A, Oberkircher PE, et al: Acute reversible lupus vasculitis of the gastrointestinal tract. Radiology 112: 569-574, Sep 1974 17. Tune BM, Leavitt TJ, Gribble TJ: The hemolytic-uremic syndrome in California: a review of 28 nonheparinized cases with long-term follow-up. J Pediatr 82:304-310, Feb 1973
671
Pediatric Radiology
18. Tune BM, Groshong T, Plumer LB, et al: The hemolyticuremic syndrome in siblings: a prospective survey. J Pediatr 85: 682-683, Nov 1974 19. Wolf BS, Marshak RH: Segl'Y\lental infarction of the small bowel. Radiology 66: 701-706, May 1956 Box 439 Letterman Army Medical Center San Francisco, Calif. 94129
•
Radiographic Features of Colitis Associated with the Hemolytic-Uremic Syndrome 1
Pediatric Radiology
Richard B. Peterson, M.D., William P. Meseroll, M.D., Gary G. Shrago, M.D., and Charles A. Gooding, M.D. Four cases of colitis associated with the prodromal phase of the hemolytic-uremic syndrome are presented. Abnormalities demonstrable on barium enema examination consist of prominent filling defects, marginal serrations, and mucosal edema. Segmental bowel dilatation and areas of stenosis may also be present. Although nonspecific in itself, this appearance of the colon when correlated with the clinical history and peripheral blood smear should enable the radiologist to suggest the diagnosis of hemolytic-uremic syndrome. INDEX TERMS: Colitis. Gastrointestinal tract, abnormalities. Gastrointestinal tract, mucosa • Hemolytic-Uremic Syndrome
Radiology 118:667-671, March 1976
•
•
syndrome (HUS) is a distinct clinical and pathological entity (11) of variable severity and undefined etiology characterized by hemolytic anemia, acute renal disease, and, usually, thrombocytopenia. Initially described in 1955 by Gasser et al. (5), this illness usually occurs in infants and young children. A prodrome of gastroenteritis with bloody diarrhea commonly precedes the more striking hematologic and renal
manifestations of the disease by several days to several weeks (10). Few examples (1) of the radiographic manifestations on barium enema examination of the colitis associated with the prodromal phase of this syndrome have been described. We wish to present the case histories and barium enema studies of 4' patients with HUS and to discuss the appearance of this associated colitis.
T
HE HEMOLYTIC-UREMIC
Fig. 1. CASE I. A. This filled barium enema study shows prominent filling defects in the cecum and ascending colon which represent "transverse ridging," probably due to colonic spasm. Marginal irregularities of the descending colon are also present. B. A spot film of the descending colon shows marginal serrations representing multiple superficial ulcerations. 1 From the Departments of Radiology, letterman Army Medical Center (R. B. P., G. G. S.), and the University of California School of Medicine (W. P. M., C. A. G.), San Francisco, Calif. Accepted for publication in September 1975. The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense. elk
667
668
RICHARD
B.
PETERSON AND OTHERS
March 1976
men with some degree of rebound but no palpable masses. Initial laboratory findings showed a hemoglobin value of 15.8 g/100 ml, hematocrit of 46%, and a white blood cell count of 23,000/mm 3 . The blood urea nitrogen was 14 mg/100 ml. A barium enema study (Fig. 2) performed on the day of admission was read as being consistent with acute ulcerative colitis. A proctoscopic examination showed granular mucosa and blood coming from above 10 cm. The patient was treated with intravenous fluids but without remission of her abdominal symptoms. On the second hospital day there was a reduction in her urine output. Two days later she became acutely distressed. She was confused and agitated, and pallor of the skin was noted. She vomited coffee-ground-Iike material. The laboratory findings showed a hemoglobin value of 9.6 g/100 ml, hematocrit of 26 %, and a white blood cell count of 41,300/mm3 . The platelet count was 40,000/mm3 . A peripheral blood smear showed schistocytes and burr cells. On the same day, the patient became anuric and required peritoneal dialysis and, later, hemodialysis. The anuric state persisted for nearly a month, followed by gradually increasing urine output. On the 45th hospital day, repeat proctoscopic and barium enema examinations were normal. An upper gastrointestinal series was also normal. On the 62d hospital day the patient was discharged with a hemodialysis regimen.
Fig. 2. CASE II. Barium study reveals narrowing of the colon lumen and marginal irregularities of the ascending and transverse colon. Asymmetric marginal indentations of the descending colon are characteristic of "thumbprinting."
CASE REPORTS CASE I (V. S.): This 10-year-old black boy was admitted because of abdominal pain, diarrhea, and vomiting of three days duration. Traces of dark red blood were noted in the numerous watery stools. Physical examination showed mild dehydration and abdominal tenderness with a mild degree of rebound. Laboratory findings on admission included a hematocrit of 45 %, a blood urea nitrogen of 30 mg/100 ml and a white blood cell count of 20,800/mm3 . Urinalysis showed 2+ proteinuria and excretory urogram was normal. Figure 1 shows the colon after a barium enema. Following treatment with intravenous fluids, the diarrhea gradually became less frequent. On the fourth hospital day, proctoscopic examination revealed mucosal inflammation and friability which was felt to be representative of ulcerative colitis. The same day the hematocrit fell to 22% with a hemoglobin value of 8.1 g/ 100 ml and two units of whole blood was given. There was thrombocytopenia of 12,000/mm3 . Urinary sediment contained 3+ protein, red cells, white cells, and casts. Shortly thereafter, peak levels of blood urea nitrogen of 64 mg/100 ml and serum creatinine of 2.6 mg/100 ml were obtained. The peripheral blood smear showed abnormal red-cell morphology, including burr cells and schistocytes. Coombs' test was negative. Urine output remained adequate throughout hospitalization. Diagnosis of HUS was made on the fifth hospital day. By the eighth hospital day, all chemical parameters started improving and continued to do so until discharge on the 18th day. A proctoscopic examination following discharge showed nonfriable mucosa, and a rectal biopsy was normal. CASE II (C. L.): This 10-year-old girl was admitted because of a three-day history of diarrhea, fever, and abdominal pain with recent onset of severe repeated bloody diarrhea and vomiting. Physical examination showed some cutaneous dehydration and a tender abdo-
CASE III (S. C.): This 2Y2-year-old white boy was admitted because of diarrhea and vomiting during the previous four days. Many of the stools contained bright red blood. Three weeks before, the child had had an upper respiratory illness which responded to ampicillin. Physical examination on the day of admission revealed that the child was lethargic and pale with mild dehydration and slight distension of the abdomen with minimal tenderness. The initial laboratory findings included a hemoglobin of 13.7 g/100 ml, a white blood cell count of 25,600/mm3 , a blood urea nitrogen of 10 mg/100 ml, and a serum creatinine of 0.6 mg/100 ml. The child was thought to have gastroenteritis secondary to a viral illness and was given intravenous fluids for dehydration. On the third hospital day there had been no improvement and the child appeared pale. The laboratory findings showed a hemoglobin value of 6.7 g/ 100 ml. The blood urea nitrogen had increased to 31 mg/ 100 ml and the serum creatinine had increased to 1.5 mgt 100 ml. The peripheral blood smear showed many fragmented cells and helmet cells. Coombs' test was negative. A barium enema study (Fig. 3) showed prominent marginal irregularities of the colon. The blood urea nitrogen and serum creatinine levels continued to climb until the seventh hospital day, when peak concentrations of 181 mg/100 ml and 5.9 mg/100 ml were obtained. Oliguria developed and persisted over several days. The child did not become anuric. Following treatment with several packed-cell transfusions and careful fluid management, a gradual improvement in both the child's clinical picture and laboratory findings was observed and he was discharged on the 20th hospital day. CASE IV (D. K.): This 5-year-old white boy exhibited nonproductive cough, fever to 39.5°C, and one episode of vomiting seven days prior to admission. These symptoms persisted and the patient was treated with penicillin. Shortly thereafter, frequent diarrheal episodes with blood streaking began. The child became pale and listless and he was admitted for treatment of dehydration. A barium enema study (Fig. 4, A) was read as being compatible with ulcerative colitis and the child was initially treated accordingly. During the hospitalization his hematocrit dropped and he required transfusions. Proteinuria and hematuria developed. Peak levels of blood urea nitrogen of 96 mg/100 ml and serum creatinine of 4.0 mg/ 100 ml were obtained; however, he continued to maintain an adequate urine output. Mild peripheral edema developed. His platelet count fell to 40,000/mm3 , and burr cells and schistocytes were seen on the peripheral blood smear. Sigmoidoscopy was performed and showed a gross area of superficial ulceration. A rectal biopsy re-
Pediatric Radiology
Fig. 3. CASE III. A. This spot film of the filled colon shows prominent "thumbprints" in the area of the splenic flexure. B. Postevacuation barium enema radiograph shows grossly abnormal colonic mucosa. There is a dilated segment of small bowel with marginal irregularity (arrows) suggesting mucosal edema.
Fig. 4. CASE IV. A. This barium enema study shows marginal irregularities and narrowing of segments Of the aescending colon. Thickened mucosal folds in the transverse colon represent edema. B. Two weeks later, a repeat barium study demonstrates a relatively normal mucosal pattern. The area of persistent narrowing in the descending colon (arrow) represents stricture formation.
669
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RICHARD B. PETERSON AND OTHERS
vealed nothing unusual. Subsequent to the diagnosis of HUS he gradually showed improvement on a restricted fluid regimen. On the 18th hospital day a repeat barium enema study (Fig. 4, B) showed marked improvement of the colon and the patient was discharged on the 22d hospital day.
DISCUSSION HUS has been recognized with ever-increasing frequency since its initial description (7, 13). The clinical entity most similar to HUS is childhood thrombotic thrombocytopenic purpura (11). The distinction between the two may be slight and represent only a difference in the distribution of the vascular lesions (3). HUS has a wide spectrum of severity ranging from asymptomatic cases (18) to death, usually from renal failure (7). The pathogenetic mechanism is generally thought to be an intravascular coagulation of unknown etiology (4) manifested by fibrin deposition in the microvasculature of the kidneys and other organs (7). The anemia of HUS occurs as a result of this microangiopathy, with the peripheral blood smear showing characteristic morphological abnormalities of the red cells (3). Typically, the disease begins in a previously healthy child who contracts gastroenteritis or, less commonly, an upper respiratory illness (10) as the initial recognized event. The gastrointestinal stage of the disease frequently resembles that seen with many viral diseases (6), and definitive treatment may be delayed because of an erroneous diagnosis. In some cases the severe bloody diarrhea and clinical presentation may mimic ulcerative colitis (2). Diagnosis is obvious once the hematologic and renal abnormalities occur but is difficult during the prodromal aspects of the disease. The course of the syndrome is variable and prognosis is related to the severity of renal involvement (7, 10). Therapy is directed toward management of the acute renal failure and correction of the hematologic abnormalities (8). The value of anticoagulant and fibrinolytic therapy in HUS is controversial (3, 7, 8, 17); however, some authors feel that administration of heparin in the early stages of the disease may be of benefit (4, 9). Unfortunately, the diagnosis is seldom, if ever, made at that time. All of the patients presented in this paper showed prominent filling defects on the barium studies, represented by "thumbprinting," "pseudotumors," and "transverse ridging." The "thumbprint" or "pseudotumor" pattern has been shown to represent submucosal hemorrhage due to vascular occlusion in the wall of the colon (14). Bar-Ziv et el. (1) suggest that this appearance may represent the early expression of the intravascular clotting which is later manifested by anemia and thrombocytopenia. "Transverse ridging" may be a manifestation of spasm (15). Both the marginal serrations which represent small ulcerations and the mucosal edema pattern seen on the barium studies are nonspecific in nature but can be found in ischemic disease of the bowel (12, 14). Bowel distension is a reflection of
March 1976
vascular compromise to the muscular layer of the gastrointestinal tract (16). With incomplete healing of the bowel wall, fibrotic changes causing stricture and stenosis will occur (15, 19). All of these radiographic manifestations reflect the underlying pathological process of ischemia, presumably due to occlusion of the intestinal microvasculature by fibrin deposits similar to those found in the kidneys. On the repeat barium enema examination shown in CASE IV (Fig. 4, B), there is resolution of all the radiographic abnormalities except the stenosis, indicating the potential reversible nature of these lesions. The radiographic findings presented above may simulate inflammatory colon diseases such as acute ulcerative or granulomatous colitis, pseudomembranous colitis, shigellosis, or salmonellosis. Although nonspecific in itself, the radiographic appearance of the colon when correlated with the clinical history and peripheral blood smear should suggest the likelihood of HUS. A most important aspect of the therapy of HUS is prompt recognition of the disease (13); the radiologist may be the first to suspect this syndrome before the severe hematologic and renal abnormalities occur. ACKNOWLEDGMENT: We wish to thank Donald R. Kirks, M.D., of Oakland, California, for supplying the roentgenograms for CASE III.
REFERENCES 1. Bar-Ziv J, Ayoub JIG, Fletcher BD: Hemolytic uremic syndrome: a case presenting with acute colitis. Pediatr Radiol 2:203205,Oct 1974 2. Berman W Jr: The hemolytic-uremic syndrome: initial clinical presentation mimicking ulcerative colitis. J Pediatr 81:275-278, Aug 1972 3. Brain MC: The haemolytic-uraemic syndrome. Semin HematoI6:162-180, Apr 1969 4. Brain MC: Microangiopathic hemolytic anemia. Ann Rev Med 21:133-144, Feb 1970 5. Gasser C, Gautier E, Steck A, et al: Harnolytlsch-urarnische Syndrome: bilaterale Nierenrindennekrosen bei akuten erworbenen harnolytischen Anarnlen. Schweiz Med Wochenschr 85: 905-909,20 Sep 1955 6. Gianantonio CA, Vitacco M, Mendilaharzu F, et al: The hemolytic-uremicsyndrome. J Pediatr 64:478-491, Apr 1964 7. Gianantonio CA, Vitacco M, Mendilaharzu F, et al: The hemolytic-uremic syndrome. Renal status of 76 patients at longterm follow-up. J Pediatr 72:757-765,Jun 1968 8 Gilchrist GS, Lieberman E, EkertH, et al: Heparin therapy in the haemolytic-uraemic syndrome. Lancet 1:1123-1126, Jun 1969 9. Katz J, Krawitz S, Sacks PV, et al: Platelet, erythrocyte, and fibrinogen kinetics in the hemolytic-uremic syndrome of infancy. J Pediatr 83:739-748, Nov 1973 10. Lieberman E: Hemolytic-uremic syndrome. J Pediatr 80: 1-16, Jan 1972 11. Lieberman E, Heuser E, Donnell GN, et al: Hemolytic-uremic syndrome. Clinical and pathological considerations. N Engl J Med 275:227-236, 4 Aug 1966 12. Margulis AR: Radiology of ulcerating colitis. Radiology 105:251-263, Nov 1972 13. PieI CF, Phibbs RH: The hemolytic-uremic syndrome. PediatrClin North Am 13:295-314, May 1966 14. Schwartz S, Boley S, Lash J, et al: Roentgenologic aspects of reversible vascular occlusion of the colon and its relationship to ulcerative colitis. Radiology 80:625-635, Apr 1963
Vol. 118
RADIOGRAPHIC FEATURES OF COLITIS
15. Schwartz S, Boley SJ, Robinson K, et al: Roentgenologic features of vascular disorders of the intestines. Radiol Clin North Am 2:71-87, Apr 1964 16. Shapeero LG, Myers A, Oberkircher PE, et al: Acute reversible lupus vasculitis of the gastrointestinal tract. Radiology 112: 569-574, Sep 1974 17. Tune BM, Leavitt TJ, Gribble TJ: The hemolytic-uremic syndrome in California: a review of 28 nonheparinized cases with long-term follow-up. J Pediatr 82:304-310, Feb 1973
671
Pediatric Radiology
18. Tune BM, Groshong T, Plumer LB, et al: The hemolyticuremic syndrome in siblings: a prospective survey. J Pediatr 85: 682-683, Nov 1974 19. Wolf BS, Marshak RH: Segl'Y\lental infarction of the small bowel. Radiology 66: 701-706, May 1956 Box 439 Letterman Army Medical Center San Francisco, Calif. 94129
