Israel Medical Association Journal

Background: Familial Mediterranean fever is an autosomal recessive disease characterized by sporadic attacks of inflammation affecting the serosal spaces. The gene associated with FMF[1] (MEFV), mainly expressed in neutrophils, was recently found to be expressed also in primary cultures of serosal origin (peritoneal and synovial fibroblasts). A C5a inhibitor, previously detected in normal serosal fluids, was recently identified in serosal cultures as well, and was found to be deficient in serosal fluids and cultures obtained from FMF patients.

Objective: To investigate the effect of colchicine (the main therapeutic agent for FMF patients) and certain inflammatory cytokines (IL-1b, TNF-a, IFN-a, IFN-g) on MEFV expression and C5a inhibitor activity in neutrophils and primary peritoneal fibroblast cultures.

Methods: Human primary peritoneal fibroblast cultures and neutrophils were studied for MEFV expression and C5a inhibitor activity, using reverse transcription-polymerase chain reaction and C5a-induced myeloperoxidase assay, respectively, in the presence and absence of colchicine and cytokines.

Results: MEFV expression in neutrophils was high and could not be induced further. Its expression in the peritoneal fibroblasts was lower than in neutrophils and could be induced using colchicine and cytokines parallel with induction of C5a inhibitor activity. Semi-quantitative RT-PCR[2] assays enabled estimation of MEFV induction by the cytokines at 10–100-fold and could not be further increased by concomitant addition of colchicine.

Conclusion: Serosal tissues, which are afflicted in FMF, express colchicine and cytokine-inducible MEFV and contain inducible C5a inhibitor activity. The relation between colchicine ability to induce MEFV and C5a inhibitor activity, and its efficacy in FMF treatment, require further investigation.

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[1] RT-PCR = reverse transcription-polymerase chain reaction

[2] FMF = familial Mediterranean fever

Background: Recent studies have suggested a possible association between Chlamydia pneumoniae infection and coronary heart disease.

Objectives: To determine titers of antibodies to Chlamydia pneumoniae in patients with acute  myocardial infraction compared with titers in several control groups.

Methods: This prospective case-control study investigated 209 individuals. We assessed the serum IgG antibody titers to Chlamydia pneumoniae in 57 consecutive patients admitted with AMI to our intensive coronary care unit during a 4 month period. A serum sample was drawn upon admission after 6 weeks. Results were compared with those of four control groups: a) patients admitted with community-acquired pneumonia (n=18), b) patients with community-acquired urinary tract infection (n=42), c) patients with angiographically normal coronary artery disease (n=44), and d) patients with stable coronary artery disease (n=48). Serum immunoglobin G antibody titers to C. pneumoniae were determined using standard micro-immunofluorescene technology.

Results: Of 57 patients with AMI, 32 (56%) had a high lgG titer to C. pneumoniae (>=1:256) on the initial test, which remained unchanged (62%) after 6 weeks. The percentage of patients with high titers was significantly lower in the control groups: 5 of 18 patients (28%) in the pneumonia group (P<0.01), 11 of 42 (26%) in the urinary tract infection group (P<0.01), 11 of 44 (25%) with normal coronary arteries (P<0.01), and 17 of 48 (35%) with stable chronic ischemic heart disease (P<0.05).

Conclusion: The detection of high titers of lgG antibodies to C. pneumoniae in many patients with AMI, compared to control groups, suggest that chronic Chlamydia pneumoniae infection plays a role in the pathogenesis of atherosclerosis and acute ischemic events.

Background: Alkaline tide is the transient increase in blood and urine pH following stimulation of gastric acid secretion. It is attributed to HC0₃ release from parietal cells in parallel with H+ secretion. The enzyme carbonic anhydrase is thought to be responsible for HC0₃ production from CO₂ and 0H in the parietal cell.

Objective: To examine the effect of pretreatment with the carbonic anhydrase inhibitor, acetazolamide, on the alkaline tide phenomenon.

Methods: Ten patients with dyspepsia and demonstrable alkaline tide were tested on three separate days. The pH and base excess were determined in arterialized venous blood before and 45 minutes after an intramuscular injection of pentagastrin. The pH of the urine was measured before and 120 mm after pentagastrin injection. Measurements were performed after pentagastrin alone on day 1 following pretreatment with acetazolamide 60 mm before pentagastrin on day 2, and after the administration of acetazolamide alone on day 3.

Results: Following the administration of pentagastrin alone, the blood base excess increased by 1.61 +0.2 mEq/L (mean + standard deviation) and the calculated alkaline tide at 45 mm was 33.99 ±4.49 mEq. On day 2 with prior adminis­tration of acetazolamide, base excess decreased by 0.21 + 0.39 mEq/L, and the calculated alkaline tide was -3.28±7.57 mEq, which was significantly lower than on day 1 (P=0 0001). On day 3, following acetazolamide alone, the base excess values decreased by 0.53~0.2 mEq/L and the alkaline tide was -10.05 +3.33 mEq there was no significant difference compared with day 2 (P= 0.44).

Conclusion: Pretreatment with acetazolamide abolished the alkaline tide induced by pentagastrin. This finding supports the view that carbonic anhydrase has a major role in the alkaline tide phenomenon.

Background: Exposure of newborn animals to high concentrations of oxygen leads to diffuse alveolar damage similar to that seen in bronchopulmonary dysplasia in human infants. Therefore, neonatal rats are a suitable practical model of hyperoxic lung damage in human infants.

Objective: To determine the involvement of tumor necrosis factor-alpha and interleukin-6 in lung injury in neonatal rats exposed to 100% O2 concentration.

Methods: A randomized controlled study was designed in which litters of term Sprague-Dawley rat pups were assigned to experimental or control groups. The pups in the experimental group were placed in 100% O2 from birth for 9 days, while the control pups were placed in room air. Twelve to 15 pups from each group were sacrificed on day 1, 3, 6, 9 and 13 after birth for bronchoalveolar lavage collection and lung histologic study. The bronchoalveolar lavage fluid was assayed for TNFα and IL-6.

Results: Newborn rats exposed to 100% O2 for the first 9 days of life showed severe pulmonary edema and hypercellularity on days 1 and 3, which then improved to nearly complete resolution on days 6 and 9. Pulmonary TNFα was produced early on O2 exposure (day 3) and pulmonary IL-6 later (days 6 and 9).

Conclusions: Hyperoxia induces sequential production of pulmonary TNFα and IL-6, which corresponds to the severity of the pathological findings and the known inflammatory and anti-inflammatory role of these cytokines.

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TNFα= tumor necrosis factor-alpha

IL-6= interleukin-6

 Background:  Pulmonary alveolar proteinosis is a rare disease in which a surfactant-like phospholipid-rich protein accumulates in the lungs. The disease is amenable to effective therapy by total lung lavage.       

Objectives: To investigate the prevalence, ethnic distribution and course of PAP  in Israel.

Methods: A countrywide survey was conducted during which pulmonologists were questioned about patients with PAP. The patients were examined and their charts, radiological images, pathological slides and physiological data were reviewed.

Results: The survey yielded 15 patients (8 females) during the period 1976–98 (14 in the last decade), giving a prevalence of 3.7x10⁶ and an incidence of 0.36x10⁶/year.

Mean age of the patients was 33±13 years (range 0.5–46 years). Seven patients were North African (two were siblings), four were from Iraq and two were Arabs; there was only one Ashkenazi Jew (a child). Symptoms at the onset were dyspnea and chest pain. Spontaneous remission occurred in at least 3 patients, and 10 patients required 1–4 bronchoalveolar lavage treatments. The subjective and physiological response was favorable, but there was less consistent radiological improvement.

Conclusion: The prevalence of PAP in Israel is approximately 3.7x10⁶. Most cases occurred in Jews who had immigrated from North Africa or Iraq, and two were siblings. The prevalence among the Arab population appears to be similar. This clustering suggests the existence of a genetic predisposition. The course of the disease appears to be similar to that reported elsewhere.

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PAP = pulmonary alveolar proteinosis