RETRACTED: A Complex Diarrhea or an Intricate Diagnosis? A Case Report

Diarrhea is not a solitary illness but is a part of different conditions. It is characterized by a rise in gut movements and an augmented liquidity of stools. Diarrhea can be acute or chronic concerning the duration of symptoms, and infectious or non-infectious concerning etiology. The differential diagnosis is noticeably large and consequently, the diagnostic tools and pathway are very multifaceted. We present the case of a 74-year-old male, with a history of acute abdominal pain, diarrhea, and fever. Several exams were made but only an examination of the stool samples came back positive for Anisakis. It is a risen infection due to augmented consumption of undercooked fish. Most cases are overlooked because of the wide-ranging variety of symptoms that make the diagnosis challenging. The diagnosis is based on the endoscopy or laparotomy. In symptomatic patients’ physical removal of the Anisakis larva using an endoscope is often curative, while anthelmintics, such as albendazole, can be used although they are not extremely efficacious. Though it is an unusual infection, clinicians should be conscious of it in patients with gastrointestinal symptoms.

Abbreviations

ALT: Alanine Transaminase; ANCA: Anti-neutrophil Cytoplasm Antibodies; AST: Aspartate Transaminase; CS: Cosenza; CT: Computed Tomography; EGD: Esophagogastroduodenoscopy; Eo: Eosinophilia; ER: Emergency Room; EVAR: Endovascular Aneurysm Repair; GGT: Gamma-glutamyl Transferase; IgE: Immunoglobulin E; SCAD: Segmental Colitis associated with Diverticulosis; UIP: Usual Interstitial Pneumonia

Introduction

Diarrhea is a communal condition that differs in severity and etiology. It is the consequence of reduced water absorption from the intestine or augmented water secretion due to a discrepancy in the normal performance of physiologic processes of the small and large intestines. It is classified into acute or chronic and infectious or non-infectious based on the length and variety of symptoms. Acute diarrhea is defined as the acute occurrence of three or more loose or aqueous feces a day lasting for 14 days or less and the most common cause is infection. On the other hand, chronic or persistent diarrhea is characterized by an episode that lasts beyond 14 days and tends to be non-infectious. Usual causes involve malabsorption, inflammatory bowel disease, and drug side effects [1]. In differential diagnosis is important to identify stool characteristics, presence or absence of related intestinal symptoms, history of the ingestion of infected food, history of water introduction, travel history, animal exposure, and predisposing factors such as hospitalization and drugs such as antibiotic use or immunosuppression [2-5]

The rising custom of eating raw, smoked, or marinated fish determines a higher risk of parasitic helminths’ zoonotic infections. Among these, it is important to underline the infection of anisakiasis that is related to various symptoms according to the localization of lesions. Patients can be asymptomatic if the larvae stay in the gastrointestinal lumen but without causing any damage. Otherwise, Anisakis larvae can enter the stomach or intestinal mucosa or rarely migrate to extra-gastrointestinal sites. Some patients can present intestinal obstruction, perforation, peritonitis, bleeding, or gastroallergic form [6].

Case presentation

A 74-year-old Italian man was admitted to the Emergency Room (ER) (Paola, CS, Italy) complaining of the onset of abdominal pain, diarrhea, and fever (temperature 38 °C). The anamnesis revealed a history of animal allergies (birds), occasional alcoholic habits, and no smoking addiction. Furthermore, he had a medical history of essential hypertension, Usual Interstitial Pneumonia (UIP) treated with Nintedanib and oxygen therapy, nonspecific colitis, and aneurysm of the infrarenal abdominal aorta treated with Endovascular Aneurysm Repair (EVAR). Physical examination revealed diffuse pain on deep abdominal palpation, while other parameters persisted normal. The patient was afebrile, the blood pressure was 130/80 mmHg, and O2 saturation was 93%. A total blood count revealed a high white blood cell count (12.72 × 10³ cells/μL). Chemical analyses revealed elevated liver transaminases (AST 117 IU/L, ALT 152 IU/L) and gamma-glutamyltransferase (GGT 128 IU/L) alkaline phosphatase (ALP 145 IU/L), alteration of electrolytes (sodium 133 mmol/L, potassium 3.30 mmol/L) while other parameters persisted normal. Blumberg, Murphy, and MC Burney’s signs were negative. The electrocardiogram and chest Computed Tomography (CT) were negative, while abdominal CT demonstrated modest thickening of the walls of the distal descending colon and the sigmoid colon, as well as known aortic aneurysm. On admission to the ER, the patient was administered pantoprazole (40 mg as a single bolus injection), Piperacillin/tazobactam (4/0,5 gr), electrolyte correction with potassium, and 1000 mL saline solution in consideration of the dehydration. During the hospitalization in our unit of Internal Medicine, a double endoscopic approach (an esophagogastroduodenoscopy EGD and a colonoscopy) was carried out. The EGD examination revealed a duodenal gastric reflux. The ileo-colonoscopy revealed a little sessile polyp and Segmental Colitis Associated with Diverticulosis (SCAD) in the descending colon and sigma. The polypoid lesion was removed, and several biopsies of the colon were performed. During hospitalization laboratory analyses disclosed negative cANCA/PR3 and pANCA/MPO, progressive appearance of absolute eosinophilia (Eo, 2.11 × 10³ cells/μL), inversion of the leukocyte formula (Eo 16.8%), and elevated total IgE levels (1776.4 IU/mL). This is why the patient underwent a coproculture that was negative and examination of the stool samples which came back positive for Anisakis (Figure 1). Following the diagnosis, albendazole (400 mg) was added to the therapeutic regimen. The patient’s health status improved shortly after pharmacological therapy. A medical check-up of the patient, performed a month after hospital discharge, confirmed no recurrence of his symptoms.

Figure 1: Microscopic examination of feces positive for Anisakis.

Discussion

Anisakiasis is a fish-borne zoonosis due to anisakid nematode, denoting a risk for humans when harsh or undercooked fish is eaten. Despite being predominant in Japan [7], the risen consumption of raw fish makes anisakiasis a public health concern for Spain, South Korea, Italy, and the USA, which are the main five countries with the highest number of published human anisakiasis cases [8]. However, the global problem of anisakiasis risks being seriously underestimated, principally because of the wide-ranging variety of symptoms that make the diagnosis challenging and the limitations of presently accessible diagnostic tools [9]. It can appear in acute (skin rashes, vomiting, diarrhea, anaphylaxis, and severe allergic reactions) and chronic forms (potentially carrying to erosive ulcers, granuloma formation, and chronic inflammation) or even asymptomatic. Furthermore, Anisakis nematodes can prompt an allergic reaction [10]. Consistent with the third-stage larvae localization and symptoms, the disease can be cataloged as gastric anisakiasis, gastro-allergic, intestinal, and extragastrointestinal anisakiasis [11,12]. The onset of the symptoms is highly variable, they can emerge either closely or up to 2 months after eating raw/undercooked seafood and lasting up to 10 years. It frequently imitated symptoms of cancer, pancreatitis, Crohn’s disease, ovarian cysts, intestinal endometriosis, epigastralgia, gastritis, gastroesophageal reflux disease, hernia, intestinal obstruction, peritonitis, and appendicitis, and because of consideration of anisakis infection as a rare condition by medical physicians [13,14], misdiagnoses are frequent.

In the present case, the patient presented abdomen pain, with concomitant fever and diarrhea. These symptoms are connected to a large group of causes, in particular, our patient was taking nintedanib which is a cause of diarrhea [15]. For this reason, at first, diarrhea was related to the assumption that this drug was interrupted without any benefit. Meanwhile, other causes of infectious and not infectious diarrhea were searched without profit. Moreover, the patient didn’t refer to the recent assumption of likely infected food. Hence, only after increasing absolute eosinophilia with inversion of the leukocyte formula and rise of total IgE levels zoonotic infections was researched leading to the diagnosis of anisakisis. This clinical case teaches us that we need to increase consciousness of fish parasites among medical specialists, have better diagnostic approaches easily available, and improve the management of anisakiasis.

Conclusion

In conclusion, in the presence of a symptom that can related to a variety of diseases, is important to search at the same time but with a “reasoned plan” for every probable cause without forgetting rare pathologies because a misdiagnosis with consequent delay in diagnosis can preclude the well-being of the patient.

Ethical considerations

This case report is completely anonymized and no identifiable information is published.

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