Israel Medical Association Journal

Background: An organ sharing system should achieve fairness and optimal graft longevity. Balancing between social and utilitarian considerations is a sensitive ethical, public and medical issue that requires a means to examine the consequences of any allocation policy or planned changes thereof.

Objective: To evaluate the performance and applicability of a computerized simulation model by examining the impact of two opposing organ allocation policies (social or utilitarian) on predicted organ distribution regarding age, waiting time, recipient sensitization measured by panel reactive antibody level and overall donor-recipient tissue matching (measured by the number of HLA antigen mismatches).

Methods: Using a computerized simulation model, virtual donors and recipients were emulated and organs were allocated according to either social algorithms or utilitarian policies. The resulting number of HLA mismatches, PRA[1], age, and waiting time distributions were compared between allocation strategies.

Results: Simulating allocation of 7,000 organs to 17,000 candidate recipients and implementing social policies yielded donor-recipient compatibility comparable to utilitarian policies (0–1 mm: 19.4% vs. 28%) while allocating 66.7% of organs to long waiters (>48 months).

Conclusion: This computerized simulation model is a valuable tool for decision-makers establishing or modifying organ allocation policies.

Background: Familial Mediterranean fever is an autosomal recessive disease characterized by recurrent attacks of fever and serositis. The disease is caused by mutations in the MEFV gene, presumed to act as a down-regulator of inflammation within the polymorphonuclear cells.

Objectives: To present the results of 412 FMF patients genotyped for three MEFV mutations, M694V, V726A and E148Q.

Results: The most frequent mutation, M694V, was detected in 47% of the carrier chromosomes. This mutation, especially common among North African Jewish FMF[1] patients, was not found in any of the Ashkenazi (East European origin) patients. Overall, one of the three mutations was detected in 70% of the carrier chromosomes. M694V/M694V was the most common genotype (27%), followed by M694V/V726A (16%). The full genotype could be assessed in 57% of the patients, and one disease-causing mutation in an additional 26%. Only one patient with the E148Q/E148Q genotype was detected despite a high carrier rate for this mutation in the Jewish population, a finding consistent with a low penetrance of this genotype. The M694V/M694V genotype was observed in 15 patients with amyloidosis compared to 4 amyloidosis patients with other genotypes (P < 0.0001).

Conclusions: Because of low penetrance and as yet other undetermined reasons, mutation analysis of the most common MEFV mutations supports a clinical diagnosis in only about 60% of patients with definite FMF.

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Background: Decreased elasticity of the aorta is associated with aging and several risk factors of atherosclerosis. The data regarding this phenomenon in patients with familial hypercholesterolemia are rather sparse.

Objectives: To evaluate non-invasively the elasticity of the proximal ascending aorta of 51 heterozygous FH[1] patients compared to 42 normal age and gender-matched controls.

Methods: Aortic elasticity was estimated by transthoracic echocardiography using the “pressure-strain” elastic modulus and aortic strain formulas.

Results: The elastic modulus score was higher in the FH group than in the controls (1.12 ± 0.91 10⁶ dynes/cm² vs. 0.65 ± 0.46 10⁶ dynes/cm² respectively, P = 0.01). This was consistent in both the pediatric (0.5 ± 0.2 10⁶ dynes/cm² vs. 0.4 ± 0.1 10⁶ dynes/cm² respectively, P = 0.009) and adult subgroups (1.3 ± 1.0 10⁶ dynes/cm² vs. 0.8 ± 0.5 10⁶ dynes/cm² respectively, P = 0.0004). Aortic strain was significantly lower in patients with FH than in controls (6 ± 4% vs. 9 ± 5% respectively, P = 0.0002). These findings reflected decreased elasticity of the proximal ascending aorta in the FH patients. In multivariate analysis, age, serum cholesterol level and serum triglycerides level were the independent predictors of the elastic modulus score, whereas age was the predictor of aortic strain.

Conclusions: The elasticity of the proximal ascending aorta is decreased in heterozygous FH patients.

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.
 

Background: Primary hyperparathyroidism in elderly patients is usually associated with additional co-morbidity that increases operative risk, and thus many geriatric patients are denied the benefit of surgery for a single parathyroid adenoma.

Objectives:  To evaluate the safety and efficacy of accurate single photon emission computed tomography sestamibi scintigraphy, enabling precise localization of a single adenoma, in the geriatric population

Methods: Twenty-two patients aged 70 years and over with biochemically proven PHPT[1] and with a single parathyroid adenoma identified by localization studies (sestamibi SPECT[2] scan and ultrasonography) underwent 23 operations over 29 months (out of a total of 140 patients operated upon during the same period). Immediate preoperative sestamibi scintigraphy and marking of focal adenoma uptake followed by intraoperative hand-held gamma probe were used for the removal of the parathyroid adenoma by unilateral minimal access surgery. Associated major co-morbid conditions and pre- and postoperative calcium, phosphorus and parathormone levels were recorded. Indications for surgery were listed and operative and postoperative complications were noted. The patients were followed for a mean period of 17.7 months using the same parameters.

Results: The 22 patients with PHPT had a mean age of 76.3 ± 5.9 years (range 70–88 years)  and a female to male ratio of 13:9. Associated co-morbidity included ischemic heart disease (n=15), hypertension (n=22), non-insulin-dependent diabetes mellitus (n=9), chronic obstructive pulmonary disease (n=3), and previous neck surgery (n=3). Mean preoperative serum calcium, phosphorous and PTH[3] were 11.7 ± 1.3 mg/dl, 2.5 ± 0.5 mg/dl and 160.9 ± 75.4 pg/ml respectively. In 20 of the 22 patients, surgery was successful in curing PHPT (91%). One patient had persistent hypercalcemia due to a missed adenoma, and repeat operation (by focused minimal access surgery) was successfully performed 2 weeks later. There were no complications and no morbidity postoperatively. Mean postoperative serum calcium, phosphorous and PTH were 9.6 ± 1.2 mg/dl, 3.0 ± 0.5 mg/dl and 35.2 ± 24 pg/ml respectively. In all patients, serum calcium levels remained normal (9.7 ± 1.3 mg/ml) after long-term follow-up (mean 17.7 ± 9.6 months).

Conclusions: Minimally invasive, radio-guided focused parathyroidectomy for a single adenoma is a safe and effective method to cure hyperparathyroidism in the elderly. Success of surgery is directly related to the surgeon's experience and to the precise localization marking provided by sestamibi scintigraphic SPECT localization and concurrent sonographic findings.

Background: Congestive heart failure is extremely common in octogenarians and is associated with severe fatigue, shortness of breath, recurrent hospitalizations, and death. These patients, many of whom are anemic, are often resistant to standard CHF[1] therapy including angiotensin-converting enzyme inhibitors, beta-blockers and diuretics.

Objectives: To examine whether correction of the anemia (hemoglobin <12 g/dl) in CHF patients lowers their resistance to therapy.

Methods: Forty octogenarians with anemia and severe resistant CHF were administered a combination of subcutaneous erythropoietin and intravenous iron sucrose.

Results: This combination therapy led to a marked improvement in cardiac function, shortness of breath and fatigue, a marked reduction in the rate of hospitalization and a stabilizing of renal function.

Conclusion: Anemia appears to be an important but ignored contributor to the progression of CHF, and its correction may improve cardiac and renal status as well as the quality of life in elderly patients.