Agenesis of the gallbladder: A multicenter case series and review of the bibliography

Gallbladder agenesis is a rare condition in pediatrics that is usually asymptomatic and represents a diagnostic challenge for physicians seeing these cases for the first time. Some patients may, however, present with symptoms that mimic other diseases of the bile ducts, and many of them undergo surgery due to such suspicion. Still, a timely diagnosis of gallbladder agenesis allows for medical treatment that is often sufficient to resolve the patient's problem. Although it is a benign condition, patients often present with other associated, more serious malformations and should be actively studied for a timely referral to other specialists. Here we describe our experience with the diagnosis and treatment of these patients and a brief review of the bibliography. We hope it will be helpful for physicians facing similar cases.

[Transition in chronic gastrointestinal diseases. From pediatric to adult care]

Technological advances and the globalization of knowledge have led to a considerable increase in the number of patients with chronic gastrointestinal disease who transition from pediatric to adult care during one of the most vulnerable life stages: adolescence. The Transition Working Group of the Gastroenterology Committee of the Sociedad Argentina de Pediatría conducted an exhaustive literature search and summoned leading specialists in the most frequent chronic pathologies from all over the country to unify criteria based on evidence and experience. As a result, a series of recommendations are proposed for the whole health team (pediatrician, pediatric gastroenterologist, nutritionist, adult gastroenterologist, psychologist, and nurse) including patients and families, to facilitate the transition process, optimize follow-up, prevent complications, and improve the quality of life of patients with chronic gastrointestinal diseases.

Congenital syphilis and hepatic infarction, a not previously reported association. A pediatric case report

Congenital syphilis is caused by Treponema pallidum infection of the fetus during pregnancy. Symptoms are variable. While endothelial damage is common, it is not usually present in congenital cases. Here we report the case of a 42-day-old infant hospitalized due to an abdominal mass. Imaging studies confirmed the presence of an injury in the left lobe of the liver without mass effect. Biopsies showed changes compatible with infarction and neonatal hepatitis. The patient's and his mother's serologies confirmed the diagnosis of congenital syphilis, and he was treated with intravenous penicillin. The liver is protected from ischemic injury by its double irrigation, but the accumulation of harmful agents may have caused this unusual presentation. Three months later, the patient was symptom-free, and the control MRI showed atrophy of the left lobe, while the rest of the parenchyma was unchanged.

Zoonotic transmission of hepatitis E virus in a pig farmer from Argentina: A case report

Hepatitis E virus (HEV) is a public health concern due to its zoonotic transmission to human, being pigs a highly recognized reservoir. We previously demonstrated HEV genotype 3 infections in pig herds from the highest commercial active region from Argentina. Here, we present a case of acute symptomatic hepatitis E in an elderly man with occupational exposure to pigs who referred regular consumption of pork and sausages. HEV infection in this patient was demonstrated by serological methods, as well as by HEV RNA detection in serum and stool samples using the HEV/MS2 duplex RT-qPCR, formerly optimized in our laboratory. We further detected HEV RNA in pig faeces from the patient´s farm. To confirm the potential role of swine in the transmission, we performed a phylogenetic analysis of all HEV RNA derived from both, the patient and the pig samples. A 303 nt region within the HEV 5 'ORF2 was amplified by nested RT-PCR and subsequently sequenced. Phylogenetic analysis showed that the strains isolated from the farmer and from his pigs presented a nucleotide identity of 100%. These results support the zoonotic transmission of circulating HEV strains and confirm this epidemiological association for the first time in Argentina.

Changing Etiologies and Prognostic Factors in Pediatric Acute Liver Failure

After the implementation of universal hepatitis A virus vaccination in Argentina, the outcome of pediatric acute liver failure (PALF) remains unknown. We aimed to identify variables associated with the risk of liver transplantation (LT) or death and to determine the causes and short-term outcomes of PALF in Argentina. We retrospectively included 135 patients with PALF listed for LT between 2007 and 2016. Patients with autoimmune hepatitis (AIH), Wilson's disease (WD), or inborn errors of metabolism (IEM) were classified as PALF-chronic liver disease (CLD), and others were classified as "pure" PALF. A logistic regression model was developed to identify factors independently associated with death or need of LT and risk stratification. The most common etiologies were indeterminate (52%), AIH (23%), WD (6%), and IEM (6%). Overall, transplant-free survival was 35%, whereas 50% of the patients underwent LT and 15% died on the waiting list. The 3-month risk of LT or death was significantly higher among patients with pure PALF compared with PALF-CLD (76.5% versus 42.5%; relative risk, 1.8 [1.3-2.5]; P < 0.001), and 3 risk factors were independently associated with worse outcome: international normalized ratio (INR) ≥3.5 (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.3-7.2]), bilirubin ≥17 mg/dL (OR, 4.4; 95% CI, 1.9-10.3]), and pure PALF (OR, 3.8; 95% CI, 1.6-8.9). Patients were identified by the number of risk factors: Patients with 0, 1, or ≥2 risk factors presented a 3-month risk of worse outcome of 17.6%, 36.6%, and 82%, respectively. In conclusion, although lacking external validation, this simple risk-staging model might help stratify patients with different transplant-free survival rates and may contribute to establishing the optimal timing for LT.

Detection of HEV in naturally infected swine from central Argentina by an optimized HEV/MS2 duplex RT-qPCR

Hepatitis E virus (HEV) is currently considered as a global health concern due to the recognition of its zoonotic transmission to humans, mainly from swine, and its association with the development of severe cases of hepatitis in human risk populations. The lack of updated data on HEV state of infection in swineherds of Argentina, and the necessity of robust technologies for its detection in complex biological samples, positions HEV as an emerging issue in public health. Here, we have optimized a RT-qPCR with internal control for a more precise and accurate HEV RNA detection in swine stool samples. We implemented this optimized molecular tool to analyse the current epidemiological scenario of HEV infection in swine from the core region of commercial activity of Argentina. A total of 135 stool samples were collected from 16 different farms and tested for HEV presence, resulting in 11 positive cases (8.1%). Phylogenetic analysis demonstrated that all of them correspond to HEV genotype 3 and that different subtypes circulate in the region. Moreover, two of the detected strains presented a high nucleotide similarity with a previously identified isolate from human sewage discharges, suggesting the zoonotic transmission of HEV to humans. Collectively, this work provides a better understanding of HEV epidemiology in Argentina while contributes to the improvement of HEV detection technologies.

Pediatric living donor liver transplant in a recipient with biliary atresia and portal vein duplication-How did we manage it?

Portal vein malformations might occur during the embryonic period, as a consequence of abnormal remodeling of vitelline veins during embryonic life. Patients suffering from biliary atresia are particularly prone to have vascular malformations; although being the most frequent indication for liver transplantation in the pediatric age, portal vein duplication has not been so far associated with biliary atresia, and to the best of our knowledge, there is no-written evidence describing how to manage it when it is first diagnosed while performing a pediatric liver transplant. Therefore, we present a recent case from our group, describing the intraoperative diagnosis of a double portal system in a patient with biliary atresia and failed Kasai. We aim to describe its surgical management, understanding that it is a real challenge to find them unexpectedly during the surgical procedure in the setting of cirrhosis and portal hypertension, particularly in small patients; therefore, by reporting this case, we aim to make readers aware about the chance of finding it, and how to managed it, to include this approach as part of the surgical armamentarium.

[Colorectal adenocarcinoma in a 5 year old girl]

Colorectal adenocarcinoma is exceptional in children, generally diagnosed in advanced stages, with worse prognosis. We report the case of a 5 year old girl with isolated hematochezia lasting two months without other findings, in whom a colorectal adenocarcinoma was confirmed by colonoscopy. Staging revealed localized disease, extending to perisigmoid fat and a few adjacent ganglia. She was treated by laparoscopic resection and adjuvant chemotherapy, being free of disease at 21 moths of follow-up.

Successful treatment of refractory autoimmune hepatitis with rituximab

Autoimmune hepatitis is a severe liver disease in which ~10% of patients do not respond to standard treatment. We describe a new rescue therapy using anti-CD20 monoclonal antibodies (rituximab). Complete remission was obtained and maintained by using low doses of immunosuppressive drugs with repeated anti-CD20 infusions.

[Portal hypertension in pediatrics: II: Hemorrhagic complications]

Bleeding from esophageal varices is the most severe complication of portal hypertension, and should be managed in specially trained centers. Vasoactive drugs, mainly octreotide, plus endoscopic treatment are able to control bleeding in 90% of the cases. Rescue treatments like TIPS and surgery should be immediately available for those who do not stop bleeding or have varices difficult to manage.

[Portal hypertension in pediatrics. I: pathophysiology and clinical aspects]

Portal hypertension causes serious and life-threatening complications. It is produced by increased resistance to blood flow through the portal axis, with a gradient to inferior vena cava higher than 5 mmHg. When this is 10 to 12 mmHg there is risk of bleeding from esophageal varices. In pediatric patients two different models exist: prehepatic (without liver disease), and intrahepatic (with liver disease), with different etiologies and prognosis. Doppler ultrasound, and liver function tests allow the distinction between them. Pediatricians should learn to recognize accurately the syndrome in order to approach the patients in a timely manner.