Israel Medical Association Journal

Background: Percutaneous tracheostomy has largely replaced surgical tracheostomy in the intensive care unit setting. Although it seems logical that surgeons continue to do tracheostomies, anesthesiologists and intensive care specialists are familiar with airway control and guide wire techniques and could replace surgeons in the performance of PDT.

Objectives: To assess the safety and effectiveness of bedside PDT[1] in the ICU[2].

Methods: We conducted a retrospective chart review of 207 patients in the ICU who underwent PDT by an intensive care physician.

Results: Subcutaneous emphysema without pneumothorax occurred in one patient. Four patients underwent surgical revision following PDT. Early bleeding (during the first 48 hours following the procedure) was the indication in two patients and late bleeding, on the 10th post-PDT day, in one. In one case PDT was converted to surgical tracheostomy due to inadvertent early decannulation. There was one death directly related to the procedure, due to an unrecognized paratracheal insertion of the tracheostomy tube followed by mechanical ventilation, which led to bilateral pneumothorax, pneumomediastinum and cardio-circulatory collapse. No infectious complications were seen at the stoma site or surrounding tissues.

Conclusions: PDT by intensive care physicians appears to be safe and should be included in the curriculum of intensive care residency.

Background: The etiology of chest pain with normal epicardial coronary arteries (cardiac syndrome X) seems to be related to endothelial cell dysfunction. Multiple factors are implicated in the pathophysiology, including evelated levels of homocysteine in the blood. Mutations in the MTHFR gene are associated with evelated levels of homocysteine.

Objectives: To test whether abnormal homocysteine metabolism is associated with syndrome X.

Methods: Forty-two women with chest pain, positive stress test and normal coronary arteries (syndrome X) and 100 asymptomatic women (controls) were studied for the C677T mutation. Vitamin B12, folic acid, and plasma levels of homocysteine were also measured. Endothelial cell function was studied in 10 patients with syndrome X and homozygosity for C677T mutation, and in 10 matched healthy controls. Folic acid (5 mg daily) was prescribed to syndrome X patients after initial measurements of ECF[1]. Following 13 weeks of treatment, ECF and blood tests were repeated and compared to baseline measurements.

Results: Homozygosity for C677T mutation was doubled in syndrome X vs. control (33%, 14/42 vs. 16%, 16/100, P < 0.02), and homocysteine levels were increased (9.16 ± 2.4 vs. 8.06 ± 2.6 μmol/L, P = 0.02). In the 10 homozygous patients, homocysteine levels decreased significantly after treatment with 5 mg/day folic acid (10 ± 3.3 vs. 5.4 ± 1.1 µmol/L, P = 0.004). Abnormal baseline ECF improved after treatment with folic acid: flow-mediated dilatation was greater (11.3 ± 7.9% vs. 0.7 ± 4.5%, P < 0.002), as was nitroglycerin-mediated dilatation (15.2 ± 9.0% vs. 5.6 ± 6.4%, P < 0.003). Frequency of chest pain episodes was significantly reduced after 13 weeks of folic acid treatment.

Conclusion: Our findings establish the association between the C677T mutation, endothelial cell dysfunction and cardiac syndrome X, and provide a novel and simple therapy for a subset of patients with syndrome X and homozygosity for the C677T mutation.

Background: Cystinuria is an autosomal recessive disease that is manifested by the development of kidney stones. Mutations in SLC3A1 cause type I disease, while mutations in SLC7A9 are associated with non-type I disease. In Israel cystinuria is especially common among Libyan Jews who suffer from non-type I disease.

Objectives: To compare clinical manifestations of patients with mutations in SLC3A1 to those with mutations in SLC7A9, and to assess the carrier rate among unaffected Libyan Jewish controls.

Methods: Clinical manifestations were evaluated in patients with mutations in SLC3A1 and in patients with mutations in SLC7A9. Carrier rates for two SLC7A9 mutations were assessed in 287 unaffected Libyan Jewish controls.

Results: Twelve patients with mutations in SLC3A1 were compared to 15 patients with mutations in SLC7A9. No differences were detected between the patients with mutations in SLC3A1 and those with mutations in SLC7A9 in relation to the age of disease onset, the estimated number of stones, the number of invasive procedures, the number of patients receiving drug therapy, or the patients’ urinary pH. Eleven of the unaffected Libyan Jewish controls were found heterozygotes for the V170M mutation, establishing a carrier rate of 1:25. The 1584+3 del AAGT mutation was not found in any of the Libyan Jewish controls.

Conclusion: Mutations in SLC3A1 and SLC7A9 cystinuria patients result in indistinguishable disease manifestations. The high carrier rate among Libyan Jews is a result of a single missense mutation, V170M.