1167

Although it maintains the manufacturer’s calibration we check the calibration against standard concentrations of 10, 50, and 80 ppm before each use. The whole system is very easy to use and has enabled us to accurately monitor the concentration of NO delivered. We suggest the use of electrochemical detection as an accurate, cheap alternative for measurement of NO. This would also ensure that every group intending to use this pulmonary vasodilator will be able to measure the concentration of NO delivered and not be limited by the cost of the technique. Paediatric Intensive Care Unit, Hospital for Sick Children, Toronto M5G 1X8, Canada

A. J. PETROS P. B. COX

D. BOHN

Distinct neurological syndrome in two brothers with hyperuricaemia SIR,- Two X-linked disorders associated with hyperuricaemia and neurological deficits in childhood have been reported. The Lesch-Nyhan-syndrome is caused by disturbed re-use of purine bases due to hypoxanthine-guanine-phosphoribosyl-transferase deficiency.1 In the second disorder the metabolic disturbance is caused by hyperactivity of phosphoribosyl-pyrophosphate (PPRP) synthetase.2 Four families with onset of the disease in childhood have been described.3-8 We describe a family with hyperuricaemia and aberrant PPRP synthetase activity in which the mother and two sons were affected. All three had facial stigmata suggestive of a genetic syndrome. Both maternal grandparents had late-onset diabetes mellitus. At age 20, hypertonia and hyperuricaemia were diagnosed in the needles, being fmer in finish. Similarly, disposable syringes, having the advantage of being unbreakable, are also being repeatedly used, often until the plastic material turns yellow because of repeated boiling. All these factors expose an unknown number of patients to the risk of various pathogens such as hepatitis and AIDS. Recently, Indian newspapers reported deliberate recycling of disposable syringes and needles, and even pavement hawkers could be spotted selling these items (figure). WHO has estimated that there could be 2 million AIDS patients in India by the turn of the century. With the meagre resources and general apathy towards such matters, the repeated use of disposable items, if unchecked, can only worsen the problem. I thank The Week, Kottayam, Kerala, India, for permission the photograph.

Department of Medicine, Calicut Medical College, Kerala, S India

to

reproduce

P. DILEEP KUMAR

Simple method for monitoring concentration of inhaled nitric oxide SIR,—We are involved in work similar to that of Dr Roberts and Dr Kinsella and their colleagues (Oct 3, pp 818, 819) and support their view that nitric oxide

(NO) may well prove useful in the persistent pulmonary hypertension of the newborn (PPHN). Because interest in NO for PPHN will now escalate, we would like to suggest a modification of the technique of delivering NO, which will make its use more accessible by greatly reducing the cost. The most expensive element of the system is the chemiluminesence monitor, which can cost between k6000 and DO 000. We are using electrochemical analysis for measuring NO. This has proved to be a simpler, cheaper, and an equally specific treatment of

alternative. We

use a

Sensor Stik Model 4586 NO gas

sensor

(Exidyne Instrumentation Technologies, Pennsylvania, USA) in a membrane-sealed electrochemical cell. NO undergoes an oxidation reaction

(NO + 2H20- > NHO3 + 3e - + 3H T) which produces a signal proportional to the gas concentration. Our Sensor Stik is cylindrical, 125 mm long and 41 mm wide, it has a liquid crystal

display, and it operates within the range 0-100 parts per million (ppm). It has a response time of less than 10 s, repeatability to within 2%, and

can

work with humidified gases in the 10-99% range.

mother; she later had gouty arthritis. She had two miscarriages, at 16 and 19 weeks, respectively; both fetuses were female. During her third pregnancy, resulting in her first affected son, gestational diabetes mellitus was diagnosed. A second child also had the disease. The father was healthy until age 47 when diabetes mellitus

developed. Both boys were born prematurely by caesarean section because of placental insufficiency and prenatal dystrophy (36th and 37th gestational week, 1390 and 1480 g). Neonatal diabetes mellitus was diagnosed in both and needed insulin treatment up to the age of 5 in the older boy. The younger boy, now aged 4, still needs a small daily dose of insulin 3 IU. Both boys had growth retardation, mental and motor retardation with absent development of speech, muscular hypotonia (especially during the first year of life), cerebellar ataxia and dysmetria, polyneuropathy with areflexia, and atrophy of the lower legs. Both boys had distinct facial features that also occurred in their mother: triangular face with prominent forehead, epicanthus, hypotelorism, beaked nose, broad mouth, and hyperopia. Electroneurography in both boys revealed a progressive axonal neuropathy with demyelinisation. Hearing was not impaired either in the boys or in the mother when investigated by routine testing. Crystals of urate could be seen in the nappies and on the tip of the penis in both boys. Biochemical investigations revealed hyperuricaemia (maximum values 815 and 667 pmol/1) and hyperuricuria (1 82 and 2-30 mmol/mmol creatinine; normal There was no evidence of urate nephropathy. Renal

Simple method for monitoring concentration of inhaled nitric oxide.

1167 Although it maintains the manufacturer’s calibration we check the calibration against standard concentrations of 10, 50, and 80 ppm before each...
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