JOURNAL OF CLINICAL MICROBIOLOGY, OCt. 1982, p. 622-626 Vol. 16, No. 4 0095-1 137/82/100622-05$02.00/0 Copyright © 1982, American Society for Microbiology Family Outbreak of Yersiniosis TOM MARTIN,l* GORDON F. KASIAN,2 AND STANLEY STEAD3 Departments of Microbiology,t Pediatrics,2 and Social and Preventive Medicine,3 University of Saskatchewan, Saskatoon, Saskatchewan, Canada 57N OWO Received 1 February 1982/Accepted 24 June 1982 Yersinia enterocolitica biotype 1, serotype 0:21 was isolated from feces or rectal washings of three members of one family in northwestern Saskatchewan. The three isolates gave positive pathogenicity tests in guinea pigs with cultures grown at 22°C as inoculum. All three cases showed clinical symptoms consistent with yersiniosis. All three cases had symptoms of diarrhea and abdominal pain, and two cases had recorded fever. In two cases, appendicitis was initially suspect. One case with ileitis and peritonitis was fatal. The environmental source of the infection was not found, but river water, milk, and person-to-person spread are discussed as possible sources of the infections. The need for microbiology laboratories to culture stool specimens specifically for Y. enterocolitica, using cold-enrichment techniques is emphasized. This family outbreak of yersiniosis provides further evidence that certain biotype 1 strains of Y. enterocolitica are pathogenic. Yersinia enterocolitica is a gram-negative ba- ferred by air ambulance to University Hospital, Saska- cillus now classified as a member of the family toon. Enterobacteriaceae. A particular characteristic Two stool specimens obtained on the second and this is its to survive and sixth days after his admission to University Hospital of organism ability were negative for ova and parasites and negative for multiply at low temperatures. virus particles by electron microscopy. An adenovirus Isolations of Y. enterocolitica in Canada have was isolated from both of these specimens. Cultures recently been reviewed by Toma and Lafleur for Salmonella spp., Shigella spp., and Campylobac- (25). These authors reviewed laboratory and ter spp. were negative. A moderate growth of Y. epidemiological findings for 1,485 strains from enterocolitica biotype 1, serotype 0:21 was obtained human sources and 495 strains from animal or by direct plating on salmonella-shigella agar of stool environmental sources isolated between 1966 specimens on March 6 and 9, 1981. and 1978. Most of the isolates from human Fluid and electrolyte balance was maintained during sources were children or adolescents in the boy's stay in the hospital. He recovered without from surgery and without antibiotics. Quebec and Ontario. Case 2. The 3-year-old sister of the boy described in The best established clinical manifestations of case 1 was admitted to the same hospital in northern infections with Y. enterocolitica are ileitis, mes- Saskatchewan on March 26, 1981. She had a high enteric lymphadenitis, and septicemia. The clini- fever, decreased appetite, and abdominal discomfort, cal aspects of infections with Y. enterocolitica but no evidence of localized abdominal tenderness. have been reviewed recently by several authors Two days after her admission to the local hospital, she (15, 28). developed watery brown diarrhea and vomiting. Intra- We report three cases of yersiniosis in mem- venous fluids were started. Four days after her admis- northwestern Sas- sion to the hospital, abdominal distension was evident, bers of a single family from and a nasogastric tube was inserted. The leukocyte katchewan due to Y. enterocolitica biotype 1, count ranged from 23,000 to 25,000, with a higher serotype 0:21. One case was fatal. proportion of neutrophilic leukocytes than normal. On March 31, 1981 the child was transferred to University CASE REPORTS Hospital, Saskatoon. Case 1. A 2-year-old boy from northwestern Sas- An abdominal X ray showed multiple, moderately katchewan developed fever, diarrhea, and vomiting. dilated, gas-filled loops of small bowel in the mid and Two days later on February 25, 1981, he was admitted upper abdomen. No gas was present in the colon or to a local hospital. His temperature on admission was rectum. Fluid appeared to be present within the perito- 40°C. His leukocyte count was 21,400 with 76% poly- neal cavity. morphonuclear leukocytes and 17% lymphocytes. On April 1, 1981, a laparotomy was done because of No localized abdominal tenderness was detected on the suspect peritonitis. At surgery, the presence of his admission to the local hospital, and the initial acute ileitis with peritonitis was confirmed. The ap- diagnosis was gastroenteritis. After 3 days, an appen- pendix had a slight degree of inflammation and was diceal abscess was suspected, and the boy was trans- removed. The terminal ileum was very inflammed and 622 VOL. 16, 1982 YERSINIOSIS: A FAMILY OUTBREAK 623 edematous. Treatment was started with gentamicin (Difco), Christensen urea agar (Difco), Simmons ci- and clindamycin. trate agar (Difco), and tryptone broth (Difco). Hydrol- Microscopic examination of the appendix showed ysis of o-nitrophenyl-o-D-galactopyranoside, phenyl- mucosal ulceration and purulent exudate in the lumen. alanine deaminase production, and motility were test- Fibrinous exudate was present on the surface. The ed in the combined medium of Giammanco and Falci deeper layers of the appendix were edematous, con- containing o-nitrophenyl-3-D-galactopyranoside and gested, and infiltrated by polymorphonuclear neutro- phenylalanine (7). Cultures in these media were incu- phils and polymorphonuclear eosinophils. bated at 35°C. In addition, colonies were tested for Aerobic and anaerobic cultures of the peritoneal motility at room temperature in the semisolid medium fluid showed no growth. Culture of a biopsy of a lymph of Edwards and Bruner (BBL) and for the absence of node of the small bowel near the terminal ileum grew oxidase with 1% tetramethylparaphenylenediamine di- Escherichia coli. The strain was resistant to ampicillin hydrochloride (Marion Scientific, Kansas City, Mo.). but sensitive to gentamicin. Cold enrichment of the Nonlactose fermenting organisms were selected as lymph node tissue for 3 weeks failed to yield Y. suspect Y. enterocolitica on the basis of the following enterocolitica. Blood and spinal fluid cultures were characteristics: oxidase negative, H2S negative, 1- negative for Y. enterocolitica. galactosidase positive (or negative at 35°C), phenylala- Two days after surgery, rectal washings were ob- nine deaminase negative, urease positive or delayed tained for culture, since the child was no longer positive, citrate negative, and motile at room tempera- passing stool. After cold enrichment for 18 days in ture but not at 35°C. selenite F medium, Y. enterocolitica biotype 1, sero- Further biochemical characterization of suspect type 0:21 was isolated from this specimen. A serum strains of Y. enterocolitica was made with either the sample obtained on April 3, 1981, gave an agglutina- Enterobacteriaceae-plus Card of the AutoMicrobic tion titer of 1/100 with the homologous strain of Y. system (Vitek Corp., St. Louis, Mo.) or by the API enterocolitica serotype 0:21. 20E system (Analytab Products, Plainview, N.Y.), Between April 2, 1981, and her death on May 13, using the protocols described by the respective com- 1981, the child developed progressive multisystem panies. failure, including hepatic and renal failure, metabolic Biotyping by Wauter's method and serotyping of encephalopathy, thrombocytopenia, and severe gas- isolates of Y. enterocolitica was kindly done by S. trointestinal hemorrhaging. Toma, National Reference Service for Yersinia, To- An autopsy revealed a retroperitoneal hematoma, ronto, Canada. with intraperitoneal hemorrhage and cutaneous ecchy- Antimicrobial susceptibility tests were performed moses, indicating a degree of disseminated intravascu- by the Kirby-Bauer method. Minimal inhibitory con- lar coagulation. centrations were determined by using microdilution Case 3. A 21-year-old woman, the mother of the trays (Micro-Scan/Alkem, Calgary, Canada). children described in cases 1 and 2, came to University Pathogenicity tests. Pathogenicity testing was done Hospital, Saskatoon, to stay with her hospitalized by the Sertny method in guinea pigs (23). A loopful of daughter. Although she was asymptomatic, a stool a 48-h culture of the test strain grown on sheep blood specimen was obtained on April 3, 1981, for culture, agar (Trypticase soy base BBL) at room temperature because she stated she had intermittent diarrhea and was introduced into the right conjunctival sac of abdominal pain in the recent past and because the guinea pigs (400 to 450 g). The left eyes of the guinea family history indicated exposure to Y. enterocolitica. pigs were not inoculated and served as a negative Direct plating of the stool specimen yielded no control. The guidelines of the Canadian Council on pathogens, but Y. enterocolitica biotype 1, serotype Animal Care for the use and care of laboratory animals 0:21 was isolated after cold enrichment of the stool were followed. The degree of conjunctivitis in guinea specimen for 10 days in phosphate-buffered saline. A pigs was graded according to the method of Schiemann serum sample obtained on April 23, 1981, gave an and Devenish (20). agglutination titer of 1/100 with the homologous strain Serological tests. Tube agglutination tests with mi- of Y. enterocolitica serotype 0:21. crotiter plates for antibody to Y. enterocolitica were kindly done by M. T. Kennedy,