Yersinia enterocolitica infection is a disease which could be seen all over the world. Pigs are described as the main reservoirs of the responsible microorganism, and the consumption of raw, undercooked pork is the primary mode of infection. Gastroenteritis is the main way of presentation with reported manifestations of watery or bloody diarrhea, vomiting, tenesmus, abdominal pain, and fever. A presumptive diagnosis rests on identifying recent consumption of suspicious food, whereas microbiological studies, as well as serologic and molecular methods, are used for the confirmation.
Yersinia enterocolitica, a Gram-negative coccobacillus, is an important pathogen [1] [2]. This bacterial microorganism causes infections all over the world, both sporadically and in the form of outbreaks [1] [2] [3]. Pigs are established as the main reservoir of Yersinia enterocolitica and unprocessed, raw, or undercooked pork meat are regarded as the primary source of infection, while contaminated water sources are also described in the pathogenesis [1] [2] [4] [5] [6]. Furthermore, cattle, goats, sheep, wild boars, cats, dogs, and small rodents are also identified as reservoirs of Yersinia enterocolitica [7]. Several outbreaks were attributed to the consumption of contaminated dairy products and tofu cheese [1] [6]. Gastroenteritis is the hallmark of Yersinia enterocolitica infection and is primarily encountered in infants and children under 10 years of age [1] [2] [3] [6] [8]. The spectrum of manifestations ranges from a benign and self-limiting abdominal discomfort to severe right lower quadrant abdominal pain (often mimicking appendicitis), tenesmus, vomiting, fever, and watery or bloody diarrhea [2] [3] [6] [7] [8] [9]. The symptoms are typically present for 7-14 days, but complications of Yersinia enterocolitica infection may be glomerulonephritis, myocarditis, reactive arthritis, and erythema nodosum [3] [6], whereas sepsis and extraintestinal dissemination of the infection are seen in rare cases [2] [3]. The presence of cirrhosis, malignancies, diabetes mellitus, and iron overload is associated with an increased risk for a systemic infection [2] [3] [8].
With a properly obtained patient history and a detailed physical examination, a presumptive diagnosis of Yersinia enterocolitica infection can be made. During the interview, the physician should assess whether the patient recently consumed undercooked or unprocessed pork or dairy products, whereas the presence of bloody stools may narrow the list of causative agents responsible for the infection. To confirm Yersinia enterocolitica as the culprit, microbiological studies need to be used. One of the first and most important investigations are stool cultures (although blood, peritoneal fluid, throat swabs, and excised mesenteric lymph nodes might also be used for cultivation) but their long turnaround time mandates the use of other methods, such as serologic and molecular studies [3] [6]. Enzyme-linked immunosorbent assay (ELISA), mainly used in the setting of chronic infections, is a reliable serologic study that can detect IgA, IgM or IgG antibodies, while polymerase chain reaction (PCR) is now regarded as an optimal procedure, being able to provide results within a very short time span [3] [6].