Predicting 22q11.2 deletion syndrome: a novel method using the routine full blood count.

BACKGROUND: 22q11.2 deletion syndrome is common affecting nearly 1 in 3000, including many with DiGeorge Syndrome and 5% of individuals with congenital heart disease. Diagnosis is important because affected patients have impaired immune function and may suffer high mortality rates if given non-irradiated blood products from graft versus host disease. Symptomatic hypocalcaemia may also occur. Our objective was to determine whether mean platelet volume (MPV), available from the routine full blood count, may be a useful and rapid indicator of 22q11.2 deletion. METHOD: A retrospective case control cohort study analysing MPV and 22q11.2 deletion status was performed in a paediatric population (n = 166) undergoing cardiac surgery between 1999 and 2005. RESULTS: Twenty children were 22q11.2 positive. The median MPV was significantly larger for the 22q11.2 positive patient group compared to the non-22q11.2 patients (10.9fL versus 8.6fL, p<0.001). The area under the curve of the receiver operating characteristics (ROC) curve of MPV was large enough (0.85) to enable the accurate prediction of 22q11.2 deletion using MPV. CONCLUSIONS: MPV is a useful screening test, involving no extra laboratory work, cost or patient discomfort. MPV>10fL is a positive predictor of the presence of 22q11.2 deletion in children with congenital heart disease (specificity 89.7%). This finding should aid rapid decision-making for ordering irradiated blood products to prevent potentially fatal transfusion-associated graft versus host disease. It will alert clinicians to monitor serum calcium levels closely to prevent hypocalcaemic seizures.

A paediatric telecardiology service for district hospitals in south-east England: an observational study.

OBJECTIVES: To compare caseloads of new patients assessed by paediatric cardiologists face-to-face or during teleconferences, and assess NHS costs for the alternative referral arrangements. DESIGN: Prospective cohort study over 15 months. SETTING: Four district hospitals in south-east England and a London paediatric cardiology centre. PATIENTS: Babies and children. INTERVENTION: A telecardiology service introduced alongside outreach clinics. MEASUREMENTS: Clinical outcomes and mean NHS costs per patient. RESULTS: 266 new patients were studied: 75 had teleconsultations (19 of 42 newborns and 56 of 224 infants and children). Teleconsultation patients generally were younger (49% being under 1 year compared with 32% seen personally (p = 0.025)) and their symptoms were not as severe. A cardiac intervention was undertaken immediately or planned for five telemedicine patients (7%) and 30 conventional patients (16%). However, similar proportions of patients were discharged after being assessed (32% telemedicine and 39% conventional). During scheduled teleconferences the mean duration of time per patient in sessions involving real-time echocardiography was 14.4 min, and 8.5 min in sessions where pre-recorded videos were transmitted. Mean cost comparisons for telemedicine and face-to-face patients over 14-day and 6-month follow-up showed the telecardiology service to be cost-neutral for the three hospitals with infrequently-held outreach clinics (1519 UK pounds vs 1724 UK pounds respectively after 14 days). CONCLUSION: Paediatric cardiology centres with small cadres of specialists are under pressure to cope with ever-expanding caseloads of new patients with suspected anomalies. Innovative use of telecardiology alongside conventional outreach services should suitably, and economically, enhance access to these specialists.

Saddle arterial embolus in a patient with Down syndrome.

We report acute thromboembolic events in a 14-year-old boy with Down syndrome and repaired atrioventricular septal defect. He presented with sudden onset of bilateral lower limb ischemia. Transesophageal echocardiography detected a thrombus in the right atrium. An arterial saddle embolus was removed following bilateral iliac embolectomy. Despite anticoagulation, he presented again with sudden bilateral lower limb ischemia and respiratory distress. Multiple pulmonary emboli and a thrombus in the right atrium were noted on imaging studies. An arterial embolus was removed from the abdominal aorta at the bifurcation. To our knowledge, this is the first report of a child or adolescent with a repaired congenital heart lesion and arterial embolism requiring embolectomy. This association and possible etiological factors are discussed.

Congenital heart disease and neuroblastoma: just coincidence?

The clinical history of a neonate with simple transposition of the great arteries in whom a metastatic neuroblastoma was diagnosed incidentally at autopsy is described, and the literature containing all 66 previously reported cases of neuroblastoma associated with congenital cardiac malformations is reviewed. One third of the described cases were classified as in situ neuroblastoma; neural crest derived cardiac lesions were present in 31%. Several possible aetiological mechanisms are discussed, and we conclude that the association of neuroblastoma with congenital cardiac malformations is multifactorial in origin. The described case represents the first reported example in which catecholamine release may have contributed to the fatal outcome of definitive congenital cardiac surgery.