Detection and pathological role of intestinal protozoa in children.

INTRODUCTION: Intestinal parasites are considered a growing public health problem, being protozoa the main cause of intestinal disease. The objective of our study is to compare the detection of intestinal protozoa by microscopy versus real-time PCR, as well as to determine the most prevalent protozoa in our environment in the paediatric population. METHOD: An observational longitudinal study was carried out, both by microscopy and real time-PCR in stool samples from children (0- 15 years) received from April 2019 to March 2021.Children were classified in two groups according if they had or not had clinical parasitosis. Microscopic examination was performed in all samples using the Ritchie concentration technique with the commercial Mini PARASEP system (Movaco-Grifols®). The presence of Cryptosporidium sp. was evaluated with the modified Ziehl-Neelsen acid-fast stain. The real-time PCR was performed to all samples using the Allplex ™ gastrointestinal parasite panel 4 (Seegene®). RESULTS: During the study period, 500 samples were received, being positive 31 (6.2%) by microscopy and 256 (51.2 %) by PCR. By microscopy, Blastocystis hominis was the most frequently observed (4.8%), followed by Giardia lamblia (1.6%), Dientamoeba fragilis (0.2%) and Cryptosporidium species (0.2%). Regarding the identification by PCR, D. fragilis (35.2%) was mainly identified, followed by B. hominis (28.1%), G. lamblia (7%) and Cryptosporidium sp. (0.8%) without finding clear differences in aetiology according to age. In the case of B. hominis and D. fragilis, there were not differences in the detection of these protozoa between the control group and children with clinical parasitosis (p = 0.11). CONCLUSIONS: Real-time PCR increases the detection of intestinal protozoa, being underdiagnosed by microscopy, especially D. fragilis, in which PCR is considered the most appropriate method for its detection.

Entamoeba histolytica liver abscess case: could stool PCR avoid it?

Background Liver abscess is the most common extraintestinal manifestation of Entamoeba histolytica. Clinical manifestations could appear after returning from an endemic area or several years after the exposure. The diagnosis usually requires microbiological confirmation. Case presentation We present a case of a 55-year-old woman diagnosed with Crohn's disease treated with immunosuppressive drugs, who was admitted to the Emergency Service with liver parenchyma abscesses. Computed tomography (CT)-guided puncture showed pus, and both Gram staining and fresh parasite visualization were negative. Hepatic pus bacteriological culture was reported as negative and parasite multiplex polymerase chain reaction (PCR) was performed, being positive for E. histolytica. The same PCR was performed on blood, pleural fluid and stool samples, all of them being positive for E. histolytica. Conclusions Reviewing the clinical history of this patient, it was observed that parasite detection in three stool samples was negative 2 months before the current admission. Due to the lack of sensitivity of the microscopy techniques, we propose to routinely perform parasite detection in stools using molecular techniques, especially in immunocompromised patients.

[Risk factors for sporadic cases of Campylobacter infection in children]. / Factores de riesgo de casos esporádicos de gastroenteritis por Campylobacter en niños.

OBJECTIVES: To identify risk factors for sporadic cases of Campylobacter infection in children aged 14 years. METHODS: We performed an age-matched, case-control study. Cases were residents of Lleida Health Region aged 6 months to 14 years old with diarrhea and positive stool isolation for Campylobacter. Information was gathered by telephone using a structured questionnaire on individual susceptibility and food and non-food exposures. A multivariate conditional logistic regression model was used to estimate adjusted odds ratios (ORa) and their 95% confidence intervals (95%CI). RESULTS: Forty-five cases and 45 controls were included in the analysis. The median age of cases was 1.6 years. Factors independently associated with disease were consumption of cooked deli meat 2 times (ORa:4.2, 95%CI:1.2-14.7), chicken 3 times (ORa:3.6, 95%CI:1.1-11.1) in the week before symptom onset, and previous antibiotic intake (ORa:4.7, 95%CI:1.1-19.6). CONCLUSIONS: Chicken meat was a risk factor for sporadic cases of campylobacteriosis in children, whether through consumption or through cross-contamination with other <> foods such as cooked deli meat.