Medium chain triglycerides in paediatric practice

Chylomicron retention disease: a rare aetiology of failure to thrive

The aetiology of failure to thrive (FTT) in children is broad, of which some conditions are extremely rare. It is important to consider these rarer conditions, especially in the setting of other concerning signs/symptoms or when there is no improvement with conventional treatment. In this case report we highlight such a rare condition-chylomicron retention disease (CRD) as an aetiology of FTT. CRD often presents with non-specific symptoms, resulting in delayed diagnosis which is established by genetic workup and histology from small intestinal biopsies. Despite being rare, CRD needs to be considered as one of the differential diagnoses after ruling out the more common causes of FTT.

Chylous Ascites: A Review of Pathogenesis, Diagnosis and Treatment

Chylous ascites (CA) is a rare form of ascites that results from the leakage of lipid-rich lymph into the peritoneal cavity. This usually occurs due to trauma and rupture of the lymphatics or increased peritoneal lymphatic pressure secondary to obstruction. The underlying etiologies for CA have been classified as traumatic, congenital, infectious, neoplastic, postoperative, cirrhotic or cardiogenic. Since malignancy and cirrhosis account for about two-thirds of all the cases of CA in Western countries, in this article we have attempted to reclassify CA based on portal and non-portal etiologies. The diagnosis of CA is based on the distinct characteristic of the ascitic fluid which includes a milky appearance and a triglyceride level of >200 mg/dL. The management consists of identifying and treating the underlying disease process, dietary modification, and diuretics. Some studies have also supported the use of agents such as orlistat, somatostatin, octreotide and etilefrine. Paracentesis and surgical interventions in the form of transjugular intrahepatic portosystemic shunt (commonly known as TIPS), peritoneal shunt, angiography with embolization of a leaking vessel, and laparotomy remain as treatment options for cases refractory to medical management.

Medium-chain fatty acids improve cognitive function in intensively treated type 1 diabetic patients and support in vitro synaptic transmission during acute hypoglycemia

OBJECTIVE

We examined whether ingestion of medium-chain triglycerides could improve cognition during hypoglycemia in subjects with intensively treated type 1 diabetes and assessed potential underlying mechanisms by testing the effect of beta-hydroxybutyrate and octanoate on rat hippocampal synaptic transmission during exposure to low glucose.

RESEARCH DESIGN AND METHODS

A total of 11 intensively treated type 1 diabetic subjects participated in stepped hyperinsulinemic- (2 mU x kg(-1) x min(-1)) euglycemic- (glucose approximately 5.5 mmol/l) hypoglycemic (glucose approximately 2.8 mmol/l) clamp studies. During two separate sessions, they randomly received either medium-chain triglycerides or placebo drinks and performed a battery of cognitive tests. In vitro rat hippocampal slice preparations were used to assess the ability of beta-hydroxybutyrate and octanoate to support neuronal activity when glucose levels are reduced.

RESULTS

Hypoglycemia impaired cognitive performance in tests of verbal memory, digit symbol coding, digit span backwards, and map searching. Ingestion of medium-chain triglycerides reversed these effects. Medium-chain triglycerides also produced higher free fatty acids and beta-hydroxybutyrate levels compared with placebo. However, the increase in catecholamines and symptoms during hypoglycemia was not altered. In hippocampal slices beta-hydroxybutyrate supported synaptic transmission under low-glucose conditions, whereas octanoate could not. Nevertheless, octanoate improved the rate of recovery of synaptic function upon restoration of control glucose concentrations.

CONCLUSIONS

Medium-chain triglyceride ingestion improves cognition without adversely affecting adrenergic or symptomatic responses to hypoglycemia in intensively treated type 1 diabetic subjects. Medium-chain triglycerides offer the therapeutic advantage of preserving brain function under hypoglycemic conditions without causing deleterious hyperglycemia.

Generalised lymphangiomatosis with chylothorax

A 9 month old boy presented with acute respiratory distress and was found to have a left pleural effusion. The chylous nature of the effusion, multiple bony lytic lesions, and splenic cysts lead to the diagnosis of congenital lymphangiomatosis with chylothorax. Surgical intervention including pleurectomy was required after unsuccessful conservative management.

Multiple nerve palsies in beta thalassaemia major

A patient with beta thalassaemia major is described who developed a lower motor neurone facial nerve palsy on the left side, together with a phrenic nerve palsy on the same side, during the course of the illness. This complication has not been reported before in haemoglobinopathies.

How should chylothorax be managed?

The management and complications of chylothorax occurring beyond the neonatal period were reviewed retrospectively. Records from 15 patients treated between 1976 and 1986 were analysed; a combination of thoracocentesis, chest drain insertion, and dietary modification were successful in abolishing chyle leakage in 10 cases. One child died from complications of cardiac surgery rather than from the chylothorax, and surgical intervention was necessary in the remaining four patients and included pleurectomy in three and thoracic duct ligation in the fourth. Lymphopenia, hypoalbuminaemia, hyponatraemia, and weight loss were the most common complications of conservative management and tended to occur in those patients with the longest duration of drainage. Postoperative recovery after pleurectomy and thoracic duct ligation was uneventful. We conclude that conservative management of chylothorax will be successful in most cases. Complications of such a policy are fairly common but rarely serious.

Reduction of bile acid loss in cystic fibrosis by dietary means

On a 'normal' diet increased faecal bile acid excretion was found in 14 of 16 children with cystic fibrosis who had steatorrhoea, but excretion was normal in 2 such children without steatorrhoea. The 16 children with steatorrhoea took 3 regimens of diet and therapy: a 'normal' diet with pancreatic enzyme supplements, a diet of reduced long-chain triglycerides with added medium-chain triglycerides, and the same diet with added pancreatic enzyme supplements. On each of these three regimens steatorrhoea and faecal bile acid loss were significantly less than on no treatment, with the lowest excretions occurring on the diet of reduced long-chain triglycerides with added medium-chain triglycerides and pancreatic enzyme supplements. Although a reduction in steatorrhoea was nearly always accompanied by a decrease in bile acid excretion, the initial bile acid loss was very variable and could not be predicted for any given degree of steatorrhoea. This suggests that at least one other factor, possibly liver disease or bile acid pool size, influences bile acid loss in the faeces.

Neonatal pneumonia associated with medium-chain triglyceride feeding supplement

The appearance of a similar pattern of multifocal pulmonary consolidation in four neonates receiving undiluted medium-chain triglyceride oil suggested a cause-and-effect relationship. This was supported by the demonstration in rabbits that the transtracheal injection of MCTO caused severe pneumonia. It is suggested that MCTO be mixed with formula before it is given to neonates.

Therapeutic approach to pancreatic extract-induced hyperuricosuria in cystic fibrosis

The relationship between the dosage of pancreatic extract and the excretion of uric acid was investigated in 29 patients with cystic fibrosis and exocrine pancreatic insufficiency. Urinary excretion of uric acid was normal in patients receiving small doses of pancreatic extracts and abnormally high in those receiving large amounts. In the latter group, normouricosuria was achieved by reducing the dose of pancreatic extract. Normal stool patterns and adequate weight gains were preserved by a diet modification that was well accepted by the patients. To eliminate the potential renal consequences of hyperuricosuria, it seems appropriate to control the need for increasing amounts of pancreatic enzymes by limiting the dietary intake of fat and maintaining a positive caloric and nitrogen balance with high intake of protein and carbohydrates and supplementation with medium-chain triglycerides.

Medium chain triglycerides for treatment of spontaneous, neonatal chylothorax. Lipid analysis of the chyle

Volume and contents of lipid and protein in the pleural fluid from a three weeks old girl with spontaneous chylothorax were studied (a) during parenteral, nonfatty nutrition and later (b) during administration of a formula (Biosorbin) containing medium chain triglycerides (MCT). The pleural fluid production could not be correlated to the treatment employed but suddenly ceased after 20 days management. Triglyceride and total esterified fatty acid concentrations in pleural fluid were high on admission when feeded with human milk, and chylomicrons and other lipoproteins were present in the chyle. During parenteral treatment a pronounced decrease in pleural fluid concentrations of triglyceride and total fatty acids occurred concomitant with a disappearance of the chylomicrons. During the following MCT diet a pronounced increase in triglyceride and total fatty acids concentrations appeared and the chylomicrons reappeared in the chyle. The cholesterol and phospholipid concentrations in the pleural fluid showed only small changes during the different treatments. No significant changes in protein and albumin concentrations of chyle were observed. It is concluded, that administration of the Biosorbin MCT formula, containing 871/2% of the fat as MCT, seems without value ih the treatment of spontaneous, neonatal chylothorax.

Relationship between bile acid malabsorption and pancreatic insufficiency in cystic fibrosis

Bile acid loss (mg/m2 24h) in the stools of 43 cystic fibrosis (CF) children with pancreatic insufficiency was 751-1 +/- 48-3, while that of six without clinical evidence of pancreatic disease (133-4 +/- 15-9) did not differ from values in 25 controls (109-8 +/- 9-8). There was a good correlation between the degree of bile acid (BA) and fat sequestration. Concomitant changes in bile acid and fat loss were observed in the one group of six patients studied on and off pancreatic enzymes as well as in a second group of seven children treated with pancreatic supplements and maintained on a normal diet followed by a low fat diet supplemented with medium chain triglycerides. Administration of NA bicarbonate led to a significant decrease in fat loss (15-8 +/- 2-7 leads to 10-3 +/- 1-9) without any simultaneous change in bile acid excretion (533-1 +/- 58-3 leads to 500-4 +/- 58-6). Qualitative bile acid patterns in controls, in infants after an ileal resection, and in patients with CF or with coeliac disease showed that the percentage of primary BA followed closely the total amount excreted except in situations where antibiotics were administered. The exact mechanism for the increased loss of BA in CF is unknown. It is found in all age groups and is related to the presence and degree of pancreatic insufficiency. The possibility that unhydrolysed triglycerides may interfere with the intestinal absorption of bile acid needs further confirmation.