Jaundice, hypertrophic pyloric stenosis, and hepatic glucuronyl transferase

Citrullinemia type I and hypertrophic pyloric stenosis in a 1-month old male infant

Citrullinemia type I (CTLN1) is an inherited urea cycle disorder, now included in most newborn screening panels in the US and Europe. Due to argininosuccinate synthetase deficiency, CTLN1 can lead to recurrent hyperammonemic crisis that may result in permanent neurologic sequelae. Vomiting in patients with urea cycle disorders may either be the result or cause of acute hyperammonemia, particularly if due to an illness that leads to catabolism. Therefore, age-appropriate common etiologies of vomiting must be considered when evaluating these patients. We present a 1-month old male infant with CTLN1 who had a 1-week history of vomiting and was discovered to have hypertrophic pyloric stenosis. This is the first documented case of an infant with CTLN1 who was later diagnosed with hypertrophic pyloric stenosis, and only the second case of concomitant disease.

The role of UGT1A1*28 mutation in jaundiced infants with hypertrophic pyloric stenosis

Hypertrophic pyloric stenosis (HPS) may be accompanied by jaundice, a condition referred to as the icteropyloric syndrome (IPS). It has long been suspected that the etiology of IPS is an early manifestation of Gilbert's syndrome (GS). Clinical features common to both GS and IPS include jaundice precipitated by fasting and improved with feeding. Prevalence of jaundice in HPS is similar to that of clinically apparent GS in the general population. Discovery of a mutation in the promoter region of the bilirubin uridine diphosphate glucuronosyl transferase gene (UGT1A1*28) as the most common cause of GS has provided a tool to determine the role of GS in IPS. The aims of this study were to determine 1) the prevalence of IPS in a large group of infants with HPS, 2) whether disease severity contributed to the manifestation of IPS, and 3) whether GS played a role in IPS. Radioactive PCR and sequencing were used to determine the presence of UGT1A1*28 mutations. We determined a prevalence of IPS of 14.3% in HPS. Infants with IPS had significantly higher levels of alkalosis than infants with HPS alone. GS mutations were 4-fold higher in IPS (43.8%) than HPS (10.7%). In conclusion, the frequency of jaundice in HPS is similar to that of clinically apparent GS in the general population. Manifestation of IPS results from a more severe degree of metabolic disturbance and the presence of GS mutations.

Diagnostic aids in the differentiation of pyloric stenosis from severe gastroesophageal reflux during early infancy: the utility of serum bicarbonate and serum chloride

This study evaluated whether serum bicarbonate levels, serum chloride levels, and other diagnostic criteria could be used to differentiate pyloric stenosis (PS) from severe gastroesophageal reflux (GER) during early infancy. The investigation was a retrospective, case-control study conducted in the emergency department of a large, academic children's hospital. Cases were 75 consecutive infants with PS confirmed in the operating room. Controls were 75 consecutive infants 12 weeks of age or younger with the diagnosis of GER whose serum electrolytes had been examined. Projectile vomiting was sensitive (0.93) but not specific (0.39) for PS. The mean serum bicarbonate level was 27.2 mmol/L for PS patients and 22.3 mmol/L for GER patients (P < .00001), and the mean serum chloride level was 95.7 mmol/L and 103.6 mmol/L for PS patients and GER patients, respectively (P < .00001). Serum bicarbonate levels of > or =29 mmol/L and serum chloride levels of < or =98 mmol/L had high positive predictive values (0.96 and 0.97, respectively) and were specific (0.99 for both) but not very sensitive (0.36 and 0.50, respectively) in identifying patients with PS. Only one patient would have been misclassified (false positive) as having PS using either of these cutoff values. These laboratory tests can also help discriminate between PS and GER when the history and physical examination fail to do so. For example, of the 20 patients with PS who did not have a pyloric mass palpated, 3 (15%) had serum bicarbonate levels of > or =29 mmol/L, and 6 (30%) had serum chloride levels of < or =98 mmol/L. In conclusion, the serum bicarbonate or serum chloride level offers a useful additional diagnostic tool in the evaluation of children presenting during early infancy with vomiting of uncertain etiology.

Variation of initial serum bilirubin rise in newborn infants with type of illness

Hyperbilirubinaemia in newborn infants is generally regarded as a problem, and bilirubin itself as toxic metabolic waste, but the high frequency in newborn infants suggests that the excess of neonatal bilirubin may have a positive function. To investigate the hypothesis that bilirubin has a role as a free-radical scavenger, the rate of rise in serum bilirubin in the first few days of life was measured in 44 infants with five illnesses thought to enhance free-radical production and in 58 control infants. The infants were selected from 2700 consecutive births by exclusion of those with factors known to affect bilirubin metabolism, including enteral feeding. The control infants were those who seemed to be ill and received treatment, including restriction of enteral feeds, but in whom no illness, or disorders not related to free-radical production, were found. The mean serum bilirubin rise was significantly lower in the combined illness group than in the control group (36.1 [95% Cl 26.9-45.3] vs 66.7 [55.9-77.5] mumol.l-1.day-1; p less than 0.0001). In subgroup analyses the mean rises in infants with circulatory failure, neonatal depression/asphyxia, aspiration syndromes, and proven sepsis were significantly lower than in controls matched for gestational age and birthweight, but rises in infants with respiratory distress and their matched controls did not differ. These findings are consistent with the hypothesis that bilirubin is consumed in vivo as an antioxidant. Such consumption may operate in vivo in addition to the standard pathways for bilirubin metabolism (production, isomerisation, and excretion).

Pyloric stenosis

Infantile pyloric stenosis is the most frequently encountered infant gastrointestinal obstruction in most general hospitals. Although the primary therapy for pyloric stenosis is surgical, it is essential to realize that pyloric stenosis is a medical and not a surgical emergency. Preoperative preparation is the primary factor contributing to the low perioperative complication rates and the necessity to recognize fluid and electrolyte imbalance is the key to successful anaesthetic management. Careful preoperative therapy to correct severe deficits may require several days to ensure safe anaesthesia and surgery. The anaesthetic records of 100 infants with pyloric stenosis were reviewed. Eighty-five per cent of the infants were male (i.e., 5.7:1 male to female ratio) 12% were prematures. Surgical correction was undertaken at an average age of 5.6 wk, and the average weight of the infants at the time of surgery was 4 kg. A clinical diagnosis of pyloric stenosis by history and physical examination alone was made in 73% of the infants presenting to The Hospital for Sick Children. All the infants received general anaesthesia for the surgical procedure and there were no perioperative deaths.

The Indian experience with hypertrophic pyloric stenosis

A study of 58 consecutive Indian infants operated for congenital hypertrophic pyloric stenosis revealed an accentuated male predominance in the incidence of the disease and far less preoperative hemetemesis as compared to that in their Western counterparts. 'Pyloric tumor' was palpable in 89% of cases. Only 34.5% of these infants were first born. Postoperative vomiting occurred in 13.8% of patients and wound sepsis was not encountered. Air contrast radiography confirmed the diagnosis in clinically doubtful cases.

Cholelithiasis in infancy: resolution of gallstones in three of four infants

Cholelithiasis in infancy is believed to be a rare finding. It is also held that all cholelithiasis in infancy has a predisposing factor such as hemolysis, prolonged fasting, congenital abnormality of the biliary tree, or the administration of TPN and is associated with severe morbidity and mortality. In the last three years, four infants at our hospital have been found on real-time ultrasonography to have gallstones. Their ages ranged from 3 weeks to 6 months. One patient had a hemolytic disease but the finding of cholelithiasis in the other three patients was incidental. A repeat sonogram in the infant with hemolysis three months after initial recognition and one day before scheduled cholecystectomy revealed spontaneous resolution of the gallstones. This led us to a conservative approach in the other three patients. Two more infants had spontaneous resolution of their gallstones and one child, now aged 16 months, is thriving with a persistent asymptomatic gallstone visible on sonogram.

Infantile hypertrophic pyloric stenosis: a review

Infantile hypertrophic pyloric stenosis is a relatively common condition and there is some recent evidence that the incidence is increasing in this country. Gastric outlet obstruction is caused by hypertrophy of the pyloric smooth muscle and the clinical presentation is with non-bilious vomiting starting at the age of 3-4 weeks. The diagnosis can usually be made by palpation of the hypertrophied pylorus. Operation has now superseded medical treatment as the treatment of choice but meticulous assessment and correction of fluid and electrolyte imbalance is essential preoperatively. The operation of pyloromyotomy as described by Ramstedt in 1912 is simple and effective, but attention to detail is necessary if minimal morbidity and zero mortality are to be achieved. Untreated, the mortality is high but, after successful treatment, these babies are healthy and normal, so that treatment is both worth while and gratifying. The aetiology is obscure; a polygenic pattern of inheritance has been shown to be a predisposing factor, but the postnatal precipitating factors are less defined. Early hopes that the hormone gastrin might prove to be the key have not been sustained by more recent research, but the role of other gastrointestinal hormones awaits clarification.

Extraordinary hyperbilirubinemia in a neonate with idiopathic hypertrophic pyloric stenosis

This case describes an extraordinarily elevated total bilirubin level that reverted to normal 9 1/2 wk after Fredet-Ramstedt pyloromyotomy. Although the etiology of jaundice occurring in patients with IHPS remains uncertain, theories implicating inhibition of the glucuronyl transferase system have been proposed. Infants with IHPS have a documented hypergastrinemia. An hypothesis is offered, illustrated by this case, to explain the inhibition of the glucuronyl transferase system with resultant hyperbilirubinemia by the hypergastrinemia of idiopathic hypertrophic pyloric stenosis.