PT  - JOURNAL ARTICLE
AU  - A A Morris
AU  - A Thekekara
AU  - Z Wilks
AU  - P T Clayton
AU  - J V Leonard
AU  - A Aynsley-Green
TI  - Evaluation of fasts for investigating hypoglycaemia or suspected metabolic disease.
AID  - 10.1136/adc.75.2.115
DP  - 1996 Aug 01
TA  - Archives of Disease in Childhood
PG  - 115--119
VI  - 75
IP  - 2
4099  - http://adc.bmj.com/content/75/2/115.short
4100  - http://adc.bmj.com/content/75/2/115.full
SO  - Arch Dis Child1996 Aug 01; 75
AB  - AIM--To assess the value and safety of fasts for investigating hypoglycaemia or suspected metabolic disease. STUDY DESIGN--Review of all diagnostic fasts performed over a 2.5 year period. SETTING--The neonatal intensive care unit and programmed investigation unit at a tertiary referral centre for endocrinology and metabolic disease. RESULTS--138 diagnostic fasts were performed during the study period. Hypoglycaemia (< 2.6 mmol/l) occurred in 54 cases but in only four did the blood glucose concentration fall below 1.5 mmol/l. One patient became unwell as a result of a fast, but prompt treatment averted any sequelae. Specific endocrine or metabolic defects were identified in 30 cases, the most common being hyperinsulinism and beta-oxidation defects. CONCLUSIONS--Fasting is safe if conducted on an experienced unit with appropriate guidelines. It continues to provide useful information for diagnosis and management, particularly in cases of hyperinsulinism. Diagnoses should, however, be established by lower risk procedures whenever possible. Thus specimens for metabolic and endocrine studies should be obtained during the presenting episode and blood acylcarnitine species should be analysed prior to fasting.