Gastroesophageal varices develop as the PSG rises to > 10 mmHg in adults and a PSG > 12 mmHg is predictive of those adults who will develop variceal hemorrhage, although pediatric confirmatory data are lacking and children may develop complications at lower gradients than adults3, 9, 10. The true incidence and prevalence of PHTN and variceal hemorrhage in pediatric patients is undereported. Current data are often limited to disease specific populations or registries. One study in long term survivors of biliary atresia without LT revealed up to two thirds of patients had PHTN and approximately 20% developed bleeding from esophageal varices11. The treatment of variceal hemorrhage is consistent across ages and includes pharmacologic measures (such as vasopressin or somatostatin) as well as endoscopic measures (such as EVL and sclerotherapy when EVL is not feasible). Refractory cases can be managed emergently with the Sengstaken-Blackmore tube. Shunt procedures (either transjugular intrahepatic portosystemic shunts or surgical) and transplantation are offered to the stabilized patient who has recurrent variceal hemorrhage not amenable to the above measures3.
Despite its routine use in adults, the primary prevention of gastrointestinal bleeding from varices remains underreported in pediatrics. Adult guidelines clearly recommend endoscopy in a patient with PHTN as the presence of varices can help determine prophylactic measures including NSBB and EVL2. These measures, have been shown to improve morbidity and mortality from variceal hemorrhage in adult patients with PHTN with no synergetic effect though and repeat endoscopy is recommended with intervals dependent on the progression of liver disease12.
Unfortunately, there is a paucity of data assessing the safety, efficacy, and outcomes of primary prophylaxis in pediatric PHTN; this includes studies on the use of both NSBB and endoscopy. As a result, there have been calls for further research acknowledging the difficulties of applying these results widely4. Guidelines, such as the Baveno VI Pediatric Satellite Symposium, have addressed this clinical question with a “do no harm“ approach until further research can be completed13. However, this recommendation requires discussion as institutions balance their patient populations with local expertise and available resources in an event that can have 6 week mortality as high as 8.8%8. While there are no published multi-centered, randomized, and prospective studies, there is a growing body of evidence that endoscopic primary prophylaxis may be safe and effective in pediatric portal hypertension.
In 2013, the French group Duché et al reported their experience in primary and secondary prophylaxis in biliary atresia6. They found that primary prophylaxis was well tolerated and recommended continued surveillance even after eradication of varices in biliary atresia. This was then followed in 2017 by a retrospective study by Duché et al for all causes of portal hypertension14. In this study they identified high risk varices (grade 3, grade 2 with red wale markings, and gastric varices) and noted that prevention of first bleed appeared to decrease morbidity and mortality. Additionally, Pimenta JR et al found endoscopic primary prophylaxis to be superior to NSBB in a small study of 26 children with cirrhosis in its ability to reduce bleeding events15. Kang KS et al found that EVL used to prevent rebleeding was safe and effective16. This is especially relevant as recent studies have shown that non-invasive measures have difficulty predicting gastrointestinal bleeding. Lampela et al. demonstrated that liver biochemistry labwork, liver stiffness, and predictive scores had difficulty predicting the presence of varices in pediatric patients with biliary atresia with similar conclusions by Angelico R et al17, 18.
Pediaatric guidelines provide a caveat that patients without easy access to appropriate levels of medical care may benefit from primary prophylaxis given the potential of rapid large volume hemorrhage19. Our practice historically established endoscopy for primary and secondary prophylaxis due to our significant rural patient population. This has led to a large pediatric population who have undergone both primary and secondary endoscopy prophylaxis with reportable clinical longitudinal data, outcomes, and complication rates to describe over a long period of time (Fig. 1a and 1b).
Most importantly, we report little complications associated with prophylactic endoscopy (Table 2). The majority of complications resolved with supportive care and only 1 case required significant intervention (a single balloon dilation for a stricture). While 18 (21%) patients of the primary prophylaxis group had breakthrough bleeding, 7 (39%) of those cases had non-variceal causes of bleeding identified at the time of endoscopy and only 6 (33%) had large varices identified at the time of bleeding. These results suggest that prophylactic endoscopy in pediatric portal hypertension may be a safe alterantive to the watchful waiting approach.
There were significant differences and similarities noted between the primary and secondary prophylactic groups. However, it is important to note that our study was not designed to evaluate whether the differences were due to treatment strategy (primary vs second prophylaxis) or other confounding factors such as inherent patient characteristics. Neither group had significant differences in age of initial presentation or diagnoses other than autoimmune hepatitis and cavernous transformation of the portal vein / portal vein thrombosis (Table 1). Initial MELD score did not show significant differences between the two groups while initial PELD scores revealed a statistically significant difference in means and a higher maximum initial PELD score in the secondary prophylaxis group. This may suggest that some young patients in the secondary group had more advanced liver disease at presentation. However, limitations to this interpretation include a debatable clinical significance of a mean PELD of 1.92 vs 6.10, that PELD is not a prognostic indicator of variceal bleeding, and the low numbers of available PELD and MELD scores in our patients that could skew results. Our primary prophylaxis group experienced a significantly decreased mean number of total endoscopies, usage of NSBB, PICU admissions, portosystemic shunts and higher rates of shunt and transplant free survival without significant complications. Again, it remains unclear if this is due to treatment strategy or patient characteristics (such as severity of disease) and should be further studied.
Our study’s strength is longtidunal safety and efficacy over a long period of time that can add to the growing body of evidence that prophylactic endoscopy should be further studied in pediatric patients with portal hypertension to determine best practices. Limitations to this study include its retrospective nature and that patients were not randomized into either group. Importantly, there is also no control group who did not receive any prophylactic endoscopy. Our center does not a have large enough group of patients with portal hypertension who did not receive any prophylactic endoscopy to meaningfully study. While our analysis can describe safety and outcomes of pediatric prophylactic endoscopy, alone it is unable to fully address the debate between prophylactic endoscopy compared to watchful waiting. Additionally, our patient population reflects a wide etiology of PHTN and recommendations for specific diseases are not easily made. There may be disease specific factors that could effect outcomes. However, comparing groups by disease resulted in too small of sample sizes to draw meaningful conclusions. Our results also may better reflect our patient pool and local expertise rather than generalizable practice.
Further studies should be performed to clearly delineate morbidity and mortality between prophylactic endoscopy of either type and watchful waiting in the pediatric setting across a spectrum of disease. Ideally, these would be prospective and multicenter given the lower volumes of patients in pediatric centers compared to adult practices. Large scale multicentre patient registries can also contirubute further to our knowledge and understanding of PHTN and its management in children. However, this study provides supporting longitudinal evidence that prophylactic endoscopy can be considered a reasonably safe protocol to manage pediatric PHTN.