Development and validation of a cost-utility model for Type 1 diabetes mellitus.

AIMS: To develop a health economic model to evaluate the cost-effectiveness of new interventions for Type 1 diabetes mellitus by their effects on long-term complications (measured through mean HbA1c ) while capturing the impact of treatment on hypoglycaemic events. METHODS: Through a systematic review, we identified complications associated with Type 1 diabetes mellitus and data describing the long-term incidence of these complications. An individual patient simulation model was developed and included the following complications: cardiovascular disease, peripheral neuropathy, microalbuminuria, end-stage renal disease, proliferative retinopathy, ketoacidosis, cataract, hypoglycemia and adverse birth outcomes. Risk equations were developed from published cumulative incidence data and hazard ratios for the effect of HbA1c , age and duration of diabetes. We validated the model by comparing model predictions with observed outcomes from studies used to build the model (internal validation) and from other published data (external validation). We performed illustrative analyses for typical patient cohorts and a hypothetical intervention. RESULTS: Model predictions were within 2% of expected values in the internal validation and within 8% of observed values in the external validation (percentages represent absolute differences in the cumulative incidence). CONCLUSIONS: The model utilized high-quality, recent data specific to people with Type 1 diabetes mellitus. In the model validation, results deviated less than 8% from expected values.

Towards consensus: history of the Australian Veterinary Association to 2000.

From its earliest beginnings in Australia in the latter part of the 19th century, the veterinary profession has striven to achieve a national voice. Well-known veterinarians were involved in the eventual establishment of the Australian Veterinary Association (AVA) in 1921. Today, all states are represented and the AVA has close contact with state and federal governments, and producer organisations. With the growth in the number of special interest groups, the AVA more than ever provides unity in diversity in order to fulfil its mission to promote the profession for the benefit of animals, the environment and the community.

Porokeratosis in association with lymphoedema.

We describe four patients in whom porokeratosis coexisted with lympoedema of the legs. A possible pathogenetic link between the two disorders is discussed, as well as the therapeutic implications and the novel physical sign of lymphoedema bulging through the porokeratotic lesions.

Epidermal naevi treated with pulsed erbium:YAG laser.

Epidermal naevi are common and can cause marked cosmetic disability. Ablative laser treatment may be successful in their removal, but may result in significant scarring. Surprisingly the erbium:YAG laser is rarely reported for this indication even though it produces minimal tissue damage. We report our experience using this laser to treat six patients with epidermal naevi. Patients (five female, one male; aged 4-41 years) underwent treatment with pulsed 2940 nm erbium:YAG laser at 0.4-0.45 J/cm(2), 2 mm spot size at 4 pulses/s. All six patients had excellent cosmetic results at follow up ranging from 6 to 60 months. The favourable results were dependent on selection of cases with superficial or small, discrete lesions which could be ablated accurately. The erbium:YAG laser is therefore an effective treatment for relatively nonverrucous or papular epidermal naevi.

Meningococcal infection in patients with the human immunodeficiency virus and acquired immunodeficiency syndrome.

Meningococcal infection is believed to be rare in HIV-positive individuals. We present 2 cases from our reference caseload within the last 10 years.

Novel mutations and polymorphisms in the Fanconi anemia group C gene.

Fanconi anemia (FA) is an autosomal recessive disorder associated with hypersensitivity to DNA cross-linking agents and bone marrow failure. At least four complementation groups have been defined, and the FA group C gene (FAC) has been cloned. We have screened 76 unrelated FA patients of diverse ethnic and geographic origins and from unknown complementation groups for mutations in the FAC gene either by chemical cleavage mismatch analysis or by single-strand conformational polymorphism (SSCP). Five mutations were detected in four patients (5.3%), including two novel mutations (W22X and L496R). Nine polymorphisms were detected, seven of which have not been described previously (663A-->G, L190F, IVS6 + 30C-->T, I312V, V449M, Q465R, and 1974G-->A). Six of the nine polymorphisms occurred in patients or controls from the Tswana or Sotho chiefdoms of South Africa and were not found in 50 unrelated European controls. Restriction site assays were established for all 8 pathogenic mutations identified in the FAC gene to date and used to screen a total of 94 unrelated FA patients. This identified only one other group C patient, who was homozygons for the mutation IVS4 + 4A-->T. This study indicates that the proportion of FA patients from complementation group C is generally likely to be less than 10%. Guidelines for the selection of FA patients for FAC mutation screening are proposed.

Measuring the fetal kidney with ultrasonography.

OBJECTIVES: To establish a normal range of measurements for the external and internal dimensions of the fetal kidney and, if possible, to correlate these measurements with gestational age. SUBJECTS AND METHODS: The external and internal dimensions of the fetal kidney were measured in 810 women selected on the grounds of obstetric, fetal or technical risk factors from a consecutive series of 1136 women attending the ante-natal ultrasonography clinic of a district general hospital. Post-natal data were obtained from medical records on 1122 newborns. The maximum of pairs of renal measurements was used for analysis. Measurements were cross-sectional in 347 cases and longitudinal in 463. The total number of measurement episodes was 2294. RESULTS: External renal dimension and gestational age were closely related, enabling accurate growth centile charts to be constructed. The correlation between renal pelvic dimension and gestational age was weak. The maximum dimension of the renal pelvis at any gestational age in 92.7% of fetuses was < 5 mm. Using longitudinal measurements, 6.5% of cases with a renal pelvic dimension of < 5 mm at the first scan measured > or = 5 mm at a subsequent scan, but 53.3% with a dimension of > or = 5 mm at the first scan also measured > or = 5 mm at the subsequent scan. CONCLUSION: It is possible to assess the growth and size of the fetal kidney according to gestational age but this does not apply to the renal pelvis. A renal pelvic dimension of > 5 mm at any gestational age is unusual and dilatation beyond this level should prompt a detailed post-natal urological investigation.

Incidence and effects of increased cerebral blood flow velocity after severe head injury: a transcranial Doppler ultrasound study I. Prediction of post-traumatic vasospasm and hyperemia.

Cerebral blood flow velocity was monitored in 50 patients with severe head injury (GCS 8 or less) within 24 h of injury and at least once daily thereafter, using transcranial Doppler ultrasonography (TCD). Delayed post-traumatic vasospasm occurred in 20, and cerebral hyperemia in another 15. Doppler velocities were higher in vasospasm, which also lasted significantly longer than hyperemia. The presence of visible blood on an early CT scan was of some value in predicting vasospasm only (accuracy 59%). Xenon-133 cerebral blood flow (CBF) was also measured within 24 h of injury. An abnormal early cerebral blood flow level, either above or below a narrow central range, was more effective than CT in predicting vasospasm or hyperemia (accuracy 80%), while the combination of an abnormal blood flow and hemorrhagic findings on CT scan helped to determine which of these would occur later. Patients with an abnormal early cerebral blood flow and hemorrhagic findings on CT were more likely to develop vasospasm--accuracy for prediction of vasospasm 73%. This distinction may be of great importance, since these different groups of patients may well need different management.