Portosystemic shunt as a cause of congenital hyperinsulinemic hypoglycemia

The Significance of Congenital Portosystemic Shunts in Congenital Heart Disease and the Bizarre Phenomenon of Alternating Portosystemic and Systemic-Portal Shunting

Congenital portosystemic shunts (CPSSs) are rare vascular anomalies characterized by abnormal connections between the portal/splanchnic veins and the systemic veins. CPSSs often occur as an isolated congenital anomaly, but they can also coexist with congenital heart disease (CHD). Owing to their myriad consequences on multiple organ systems, familiarity with CPSS is of tremendous importance to the care of patients with CHD. The rationale and timing for interventions to embolize CPSS in this scenario are discussed. Specific shunt embolization techniques are beyond the scope of this article.

Intrahepatic portosystemic shunts, from prenatal diagnosis to postnatal outcome: a retrospective study

OBJECTIVE

Congenital intrahepatic portosystemic shunts (IHPSS) are rare vascular malformations resulting in blood bypassing the liver to the systemic circulation. Previous studies included symptomatic patients diagnosed postnatally, but the outcome of IHPSS diagnosed prenatally is rarely reported. We present a cohort of children prenatally diagnosed with IHPSS and report their natural course and outcome.

METHODS AND DESIGN

This was a retrospective study of all fetal cases diagnosed by ultrasound with IHPSS between 2006 and 2019 at a single tertiary centre which were prospectively followed up at the paediatric gastroenterology unit. The postnatal outcome was compared between patients with a single versus multiple intrahepatic shunts.

RESULTS

Twenty-six patients (70.3% boys) were included in the study, of them, eight (30.8%) patients had multiple intrahepatic shunts. The median gestational age at diagnosis was 29.5 weeks. Growth restriction affected 77% of the cohort. Postnatally, spontaneous shunt closure occurred in 96% of patients at a median age of 7.5 months (IQR 2.2-20 months). Failure to thrive (FTT) and mild developmental delay were observed in eight (30.8%) and seven (26.9%) patients, respectively. FTT was significantly more prevalent in patients with multiple shunts compared with patients with a single shunt (62.5% vs 16.7%, p=0.02); however, the rate of shunt closure and age at time of closure were similar between these groups. All patients survived with limited to no sequelae.

CONCLUSIONS

IHPSS usually close spontaneously by 2 years of age. Children with prenatally detected IHPSS may develop FTT and mild developmental delay. Close surveillance at a paediatric gastroenterology unit may be beneficial.

Abnormal glucose homeostasis and fasting intolerance in patients with congenital porto-systemic shunts

In physiological glucose homeostasis, the liver plays a crucial role in the extraction of glucose from the portal circulation and storage as glycogen to enable release through glycogenolysis upon fasting. In addition, insulin secreted by the pancreas is partly eliminated from the systemic circulation by hepatic first-pass. Therefore, patients with a congenital porto-systemic shunt present a unique combination of (a) postabsorptive hyperinsulinemic hypoglycaemia (HH) because of decreased insulin elimination and (b) fasting (ketotic) hypoglycaemia because of decreased glycogenolysis. Patients with porto-systemic shunts therefore provide important insight into the role of the portal circulation and hepatic function in different phases of glucose homeostasis.

Reactive hypoglycemia owing to an intrahepatic congenital portosystemic shunt in an older patient

An 85-year-old woman was admitted to our hospital because of hypoglycemia and impairment of consciousness several hours after breakfast. Because the hypoglycemia predominantly occurred 2-4 h after meals, we diagnosed reactive hypoglycemia. An oral glucose tolerance test showed prolonged hyperinsulinemia following the postprandial hyperglycemia, with a subsequent rapid decrease in blood glucose concentration. The post-stimulus plasma C-peptide concentration was relatively low compared to the plasma insulin concentration. Abdominal computed tomography revealed an intrahepatic congenital portosystemic shunt (CPSS). On the basis of these findings, we concluded that the reactive hypoglycemia was induced by the CPSS, via a reduction in hepatic insulin extraction. Treatment with an alpha-glucosidase inhibitor resolved the reactive hypoglycemia. CPSS comprises anomalous vascular connections between the portal vein and the systemic venous circulation, and reactive hypoglycemia is a rare complication of this malformation, which has most frequently been reported in children, with only a few cases reported in adults. However, this case indicates that even in adult patients, imaging studies should be conducted to rule out CPSS as the cause of the reactive hyperglycemia.

Congenital Portosystemic Shunts: Variable Clinical Presentations Requiring a Tailored Endovascular or Surgical Approach

Congenital portosystemic shunts (CPSS) are rare developmental anomalies resulting in diversion of portal flow to the systemic circulation. These shunts allow intestinal blood to reach the systemic circulation directly, and if persistent or large, may lead to long-term complications. CPSS can have a variety of clinical presentations that depend on the substrate that is bypassing hepatic metabolism or the degree of hypoperfusion of the liver. Many intrahepatic shunts spontaneously close by 1 year of age, but extrahepatic and persistent intrahepatic shunts require intervention by a single session or staged closure with a multidisciplinary approach. Early detection and appropriate management are important for a good prognosis. The aim of this case series is to describe the varied clinical presentations, treatment approaches, and outcomes of 5 children with CPSS at our institution. Management of these patients should involve a multidisciplinary team, including interventional radiology, surgery, hepatology, and other medical services as the patient's clinical presentation warrants. Regardless of clinical presentation, if a CPSS persists past 1-2 years of age, closure is recommended.

Presentation, Management, and Outcome of Congenital Portosystemic Shunts in Children: The Boston Children's Hospital Experience

OBJECTIVES

Congenital portosystemic shunts (CPSS) are rare vascular malformations. We describe presentations, complications, associations, and outcomes of CPSS at Boston Children's Hospital (BCH).

METHODS

This was a retrospective review of children with CPSS at BCH from 2000 to 2020.

RESULTS

Twenty-nine patients had CPSS (17 girls): 14 extrahepatic (EH) and 15 intrahepatic (IH). At diagnosis, 15 were ≤5 days, 7 <1 year, and 7 >1 year (range 1-19). Median follow-up duration was 5.2 years (interquartile range [IQR] 1.6-10.9) in EH and 2.2 years (0.2-4.2) in IH CPSS. The most common presentation was antenatal ultrasound 13 (45%) followed by hyperammonemia 10 (34%), whereas 6 (21%) were asymptomatic. Complications were noted in 17 (12/14 EH vs 6/15 IH, P = 0.008). Associated anomalies were present in 25 (14/14 EH vs 11/15 IH, P = 0.10). Spontaneous closure was observed in 8 (28%) patients with IH CPSS, all <12 months of age. Ten patients underwent shunt closure 3 (30%) by interventional radiology (IR) and 5 (50%) by surgery, whereas 2 (20%) required both. After therapeutic closure; 8 had improvement, 1 had portal hypertension, and 1 had sepsis and thrombosis. The remaining 11 patients, 8 (42%) were followed without closure: 6 of 8 (75%) EH versus 2 of 11 (18%) IH ( P = 0.02), 2 lost follow-up and 1 with complicated EH CPSS died, unsuitable for therapeutic closure.

CONCLUSIONS

CPSS may be asymptomatic or present with complications. Spontaneous closure of IH shunts may occur in infancy, thus therapeutic closure may be deferred until age ≥ 2 years. IR and surgical closure of CPSS are associated with improvement in the majority of cases.

Congenital Portosystemic Shunts: Current Diagnosis and Management

Congenital portosystemic shunts are increasingly recognized in several settings and at any age. The following are some of the most common presentations: prenatal ultrasound, neonatal cholestasis, incidental finding on abdominal imaging, or systemic complications such as unexplained cardiopulmonary or neurological disease, or the presence of liver nodules in a noncirrhotic liver. The purpose of the present review is to summarize clinical presentation and current recommendations for management, and highlight areas of future research. Illustrative examples from the veterinary literature complement our current lack of knowledge of this rare malformation often masquerading as a multisystem disease.

Congenital intrahepatic portocaval shunts and hypoglycemia due to secondary hyperinsulinism: a case report and review of the literature

Background

Congenital portosystemic shunts present with various associated complications, such as other congenital malformations, hyperammonemia, or hepatopulmonary syndrome. Few cases of associated hypoglycemia have been reported so far and our case, to the best of our knowledge, describes the most severe extent of hypoglycemia.

Case presentation

We describe the case of a newborn Arab boy with two intrahepatic portosystemic shunts, resulting in severe and persistent hypoglycemia, due to which one of the shunts was closed by interventional radiology whereas the other shunt had already closed spontaneously.

Conclusions

Because he showed elevated levels for insulin and prolonged high insulin levels in an oral glucose tolerance test, our case supports the theory that portocaval shunts cause a reduced hepatic insulin reduction due to the high blood volume bypassing the liver. This case provides further insights into glucose regulation mechanisms of the liver and we suggest a consistent screening for hypoglycemia in patients with congenital portosystemic shunts.