Loss to follow-up after arthroplasty: a new use for registry data.

We assessed the outcome of patients who were lost to follow-up after arthroplasty by a single surgeon. The aim was to validate the surgeon's data set with the Australian Orthopaedic Association National Joint Replacement Registry and determine the outcome of those patients lost to follow-up. Prospective data on patient demographics, operative details and outcomes of the surgeon's 1192 primary unicompartmental knee arthroplasty (UKA) procedures were analysed. There were 69 knees in patients who were lost to follow-up, among whom the Registry identified 31 deaths and eight revisions. The cumulative percentage revision (CPR) at seven years using the additional Registry data was 8.8% (95% confidence interval (CI) 7 to 11). Using the surgeon's data, the CPR at seven years was 8% (95% CI 6.3 to 10.1) for the best-case scenario where loss to follow-up was excluded, and 16% (95% CI 13.8 to 19.4) for the worst-case scenario, where all patients lost to follow-up were deemed to have been revised. There was a significantly higher mortality rate in those patients lost to follow-up. This study demonstrates that a national joint registry can be used by individual surgeons to establish more accurate revision rates in their arthroplasty patients. This is expected to facilitate a more rigorous audit of surgical outcomes by surgeons and lead to more accurate and uniform reporting of the results of arthroplasty in general.

Dietary calcium in galactosaemia.

The diets of 19 galactosaemic patients were assessed for calcium and phosphorous intake. Despite the use of infant soya formula or calcium-supplemented soya milk the reference nutrient intake (RNI) for calcium was only met in 26% of the group; all patients met > 100% of the RNI for phosphorous. The regular assessment of the diets of galactosaemia patients is recommended as the milk-free nature of the diet can lead to an inadequate calcium intake. Lactose-free calcium supplements should be prescribed if the diet alone is inadequate.

Wechsler subscale IQ and subtest profile in early treated phenylketonuria.

AIM: Mildly depressed IQ is common in treated phenylketonuria. This study explored whether a particular intellectual ability profile typifies early and continuously treated phenylketonuria and whether component skills comprising the IQ relate to socioeconomic and treatment factors. METHODS: IQ scores were collected retrospectively from variants of the "Wechsler intelligence scale for children" performed at age 8 on 57 children with early treated, classic phenylketonuria. The mental ability pattern underlying IQ was investigated by analysing subscale and subtest scores and dietary factors, such as historical phenylalanine blood concentrations. RESULTS: The children's mean full scale IQ of 91.11 was significantly below the healthy population norm. There was a significant discrepancy between their mean verbal IQ (94.65) and mean performance IQ (89.42), suggestive of a spatial deficit, but the data did not support a biochemical or sociological explanation. Individual Wechsler subtests had no distinctive pattern. Phenylalanine control at age 2 was predictive of overall IQ. At this age, children with annual median phenylalanine < 360 micromol/litre (recommended UK upper limit) had a mean IQ 10 points higher than those above. CONCLUSIONS: Early and continuous treatment of phenylketonuria does not necessarily lead to normalisation of overall IQ. Verbal intelligence in the primary school years appears to normalise if blood phenylalanine is maintained below 360 micromol/litre in infancy, but spatial intelligence may remain poor. However, the discrepancy in skill development is not the result of social status or treatment variables. Perhaps weak spatial intelligence is an ancillary effect of a protective rearing style occasioned by the dietary treatment regimen.

Intra-arterial calcium stimulation test in the investigation of hyperinsulinaemic hypoglycaemia.

OBJECTIVE: To investigate the use of a calcium infusion test in the diagnosis and localisation of insulin secreting tumours in children. PATIENTS: Three patients with persistent hypoglycaemia of infancy (PHHI). PROCEDURE: During planned selective coeliac and mesenteric arteriography, serial samples were taken from a catheter in the right hepatic vein for insulin measurement following the injection of calcium gluconate. RESULTS: In all three children, selective intra-arterial calcium stimulation produced a significant rise in plasma insulin and was of value in localising the pancreatic abnormality in one child. In vitro studies on islets of Langerhans isolated from this patient following partial pancreatectomy showed unresponsive intracellular calcium signalling of the cells when stimulated with high extracellular concentrations of glucose and potassium or with sulphonylurea drugs (tolbutamide), but normal responsiveness to increasing extracellular calcium concentrations. CONCLUSIONS: The findings suggest a functional abnormality of the calcium channel in PHHI and provide a rationale for the reported efficacy of channel blocking drugs in this condition. The role of selective intra-arterial calcium stimulation in the diagnosis of hyperinsulinaemic hypoglycaemia in childhood warrants further investigation.

Neonatal meningococcal conjunctivitis associated with meningococcal meningitis.

Two infants are described in whom identical strains of meningococcus were isolated from both the eyes and the cerebrospinal fluid. This suggests that the eye may be a portal of entry in at least some cases of perinatally acquired neonatal meningococcal disease and has important implications for the management of purulent conjunctivitis in the newborn.

Neonatal renal candidal bezoar.

Renal candidal bezoar is uncommonly encountered in neonatal intensive care. An affected neonate who improved only after surgical removal of obstructive fungus from the renal pelvis and local irrigation with amphotericin B is described. The need for early consideration of surgical intervention is stressed.

Neurological deterioration in young adults with phenylketonuria.

7 patients with phenylketonuria who developed neurological disability in adolescence or early adult life are described. 4 had been diagnosed by routine neonatal screening and started a low phenylalanine diet in infancy. 3 were diagnosed in early childhood because of developmental delay, and then started dietary treatment. Dietary control deteriorated in later years and was withdrawn in mid to late childhood. The late neurological deterioration cannot be directly ascribed to poor compliance with or cessation of dietary treatment in this small, retrospective study--but other likely causes have been excluded and 2 patients showed a striking clinical improvement when a strict diet was resumed. Serial magnetic resonance images from one of these patients show abnormalities that appeared after cessation of dietary treatment and resolved after diet was resumed. If these findings are confirmed, strict dietary control into adult life would be indicated for at least some patients with phenylketonuria.