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Meir Mouallem

Publications and source records attributed to Meir Mouallem.

11 recordsLinked to original sources

[Costeff syndrome: a syndrome that was described in Israel and the responsible gene discovered by an Israeli doctor].

Costeff syndrome or 3-methylglutaconic aciduria type 3, was described by a group of Israeli doctors in 1989. Since then more than 40 patients were described. Most of the patients are of Iraqi-Jewish origin. The clinical abnormalities are bilateral optic atrophy, extrapyramidal signs, spasticity ataxia, dysarthria and mild cognitive deficit. Recently, the gene responsible for this disorder, OPA3 gene was identified. This gene was also discovered by an Israeli doctor. This is a case history of a patient with Costeff syndrome presenting the characteristics of this syndrome and the gene that causes this disease.

Adult↗

Resolution of hypertension during pregnancy in familial hyperkalemia and hypertension with the WNK4 Q565E mutation.

OBJECTIVE: Secondary hypertension during pregnancy usually carries high maternal and fetal morbidity and mortality rates. A rare form of monogenic hypertension is familial hyperkalemia and hypertension, which is caused by mutations in the kinases WNK1 or WNK4 and other unknown molecular defects. The purpose of the study was to examine the course of pregnancy in hypertensive women with familial hyperkalemia and hypertension. STUDY DESIGN: We prospectively studied 2 pregnancies of a woman with familial hyperkalemia and hypertension and the Q565E WNK4 mutation (pregnancies 1 and 2) and retrospectively studied the course of 2 pregnancies in another woman who was an affected member of this largest family described in the literature. RESULTS: Both women had hypertension (170-190/105-110 mm Hg), hyperkalemia (5.3-6.0 mmol/L), and hypercalciuria, all of which were well controlled by thiazides. During pregnancies, thiazides were discontinued; throughout the pregnancy, the blood pressure remained normal at 120 to 130/75 to 85 mm Hg; however, hyperkalemia and hypercalciuria, which were documented in pregnancies 1 and 2, persisted. Renin and aldosterone levels (which were measured in pregnancies 1 and 2) rose towards their end. Four normal infants were born. A woman with familial hyperkalemia and hypertension of unknown molecular defect who had 2 pregnancies with hypertension exacerbation and premature deliveries was described previously. CONCLUSION: In familial hyperkalemia and hypertension with the WNK4 mutation, pregnancy ameliorates hypertension; however, hyperkalemia and hypercalciuria persist. This dissociation may shed light on the pathogenesis of familial hyperkalemia and hypertension, on pregnancy-related hypertension, and on the mechanism of action of WNK4 kinase, a major regulator of cellular ion transport.

Adult↗

[Streptococcus group C bacteremia and meningitis].

Group C streptococci are common causative agents of infections in animals, but a rare cause of bacteremia and meningitis in humans. Severe infections caused by this bacterium are associated with high morbidity and mortality rates. This article presents a case study of a young patient who suffered from bacteremia and meningitis that were caused by streptococcus group C. The clinical manifestations, prognosis and treatment options of this kind of infection are discussed.

Adult↗

Acute renal embolism. Forty-four cases of renal infarction in patients with atrial fibrillation.

Acute renal embolus is rarely reported in the medical literature; thus, accurate data regarding presentation, laboratory tests, diagnostic techniques, and treatment are lacking. To better define this condition, we examined the medical records of all patients admitted to Kaplan Medical Center and Sheba Medical Center in central Israel from 1984 to 2002 who had a diagnosis of renal infarction and atrial fibrillation. We noted demographic, clinical, and laboratory parameters; method of diagnosis; treatment received; and patient outcome. We identified 44 cases of renal embolus: 23 females and 21 males, with an average age of 69.5 +/- 12.6 years. Thirty (68%) patients had abdominal pain, and 6 (14%) had a previous embolic event. Nine patients were being treated with warfarin on admission, 6 (66%) of whom had an international normalized ratio (INR) < 1.8. Hematuria was present in 21/39 (54%), and 41 (93%) patients had a serum lactate dehydrogenase (LDH) level > 400 U/dL. The mean LDH was 1100 +/- 985 U/dL. Diagnostic techniques included renal isotope scan, which was abnormal in 36/37 cases (97%); contrast-enhanced computed tomography (CT) scan, which was diagnostic in 12/15 cases (80%); and ultrasound, which was positive in only 3/27 cases (11%). Angiography was positive in 10/10 cases (100%). Twenty-three (61%) of 38 patients had normal renal function on follow-up. The 30-day mortality was 11.4%. Renal embolus was diagnosed mainly in patients aged more than 60 years, some of whom had a previous embolic event. Most of those receiving anticoagulant therapy had a subtherapeutic INR. Abdominal pain was common, as well as hematuria and an elevated LDH. These patients are at risk of subsequent embolic events to other organs. The most sensitive diagnostic technique in this population is a renal isotope scan, but contrast-enhanced CT scan requires further assessment.

Acute Disease↗

Hypercalciuria in familial hyperkalemia and hypertension accompanies hyperkalemia and precedes hypertension: description of a large family with the Q565E WNK4 mutation.

Familial hyperkalemia and hypertension (FHH; pseudohypoaldosteronism type II) is an autosomal dominant disorder characterized by hyperkalemia, hypertension, and low renin. WNK1 kinase overexpression and WNK4 kinase inactivating missense mutations cause FHH. When expressed in frog oocyte, WNK4 inhibits Na-Cl cotransporter surface expression, and WNK1 relieves this inhibition. We have reported hypercalciuria in subjects with the WNK4 Q565E mutation. In contrast, in subjects with WNK1 overexpression, normocalciuria was found. Here we report a major extension of our previously described kindred that contains 34 subjects, 18 of them affected by the mutation. Hypertension was diagnosed in 13 affected subjects at the age of 31 +/- 12 yr. Five of the affected or obligatory affected subjects had stroke, in four at the age of 50-62 yr. Seven subjects with FHH were diagnosed 27 yr previously. All four subjects who were normotensive at diagnosis became hypertensive during follow-up. The mean time between detection of hyperkalemia and appearance of hypertension was 13 yr. In the extended kindred, compared with the unaffected subjects, affected subjects had hyperkalemia, low transtubular potassium gradient, hyperchloremia, low bicarbonate, higher aldosterone, and marked suppression of renin. Urinary calcium levels in affected and unaffected subjects were 0.85 +/- 0.27 and 0.28 +/- 0.12 mmol/mmol creatinine, respectively (P < 0.0001). Hypercalciuria was accompanied by lower serum calcium levels [9.44 +/- 0.15 vs. 9.81 +/- 0.31 mg/dl (2.36 +/- 0.04 vs. 2.45 +/- 0.08 mmol/liter); P = 0.01], supporting a mechanism of renal calcium leak. The six affected, currently normotensive subjects had the same degree of hyperkalemia, hypercalciuria, and low renin as the affected hypertensive subjects. We conclude that in FHH with WNK4 mutations, with time all affected subjects will apparently develop hypertension. Hypercalciuria accompanies hyperkalemia, and both precede hypertension. Based on the recent findings that WNK4 regulates the renal outer medullary potassium channel as well as epithelial Cl(-)/base exchanger and the Na(+)-K(+)-2Cl(-) cotransporter, we suggest that WNK4 interacts with a calcium channel or transporter.

Adult↗

[Beer potomania].

Beer potomania is a rare syndrome which is manifested by severe hyponatremia and various mental changes related to binge beer drinking and poor dietary intake. This article is a case study describing an alcoholic that was admitted because of this syndrome. We also discuss the pathophysiology of hyponatremia in alcoholics and especially in the syndrome of beer potomania.

Adult↗

Pericardial tamponade-associated hyponatremia.

We describe a 58-year-old patient with adenocarcinoma of the lung who suffered from severe weariness that was attributed to hyponatremia. The cause of hyponatremia was found to be a malignant pericardial effusion that caused pericardial tamponade. The hyponatremia was corrected rapidly after the evacuation of the malignant effusion. The pathogenetic mechanisms of hyponatremia secondary to pericardial effusion are discussed.

Adenocarcinoma↗

Clopidogrel-induced systemic inflammatory response syndrome.

Clopidogrel bisulfate, a widely used inhibitor of platelet aggregation, is considered at least as safe as aspirin. We describe a patient who developed a systemic inflammatory response syndrome consisting of high fever, tachycardia, cellulitis-like rash, impaired liver function, and mild leukopenia after receiving clopidogrel before coronary angiography and stent implantation. The reaction resolved promptly after withdrawal of the drug and recurred shortly after a rechallenge dose was administered, thus making the diagnosis of a clopidogrel-induced reaction highly probable. Recognition of this clopidogrel-induced syndrome is extremely important, both for rapid discontinuation of the offending drug and for avoidance of unnecessary drug therapy or invasive procedures.

Clopidogrel↗

Gastroenteritis-associated hyperamylasemia: prevalence and clinical significance.

BACKGROUND: Serum amylase levels can be elevated in various pathological conditions. However, acute gastroenteritis has not been widely recognized as a cause for hyperamylasemia. PATIENTS AND METHODS: We conducted a retrospective study of amylase results for all patients hospitalized or discharged from the emergency department with a diagnosis of gastroenteritis from April through November 1999. Patients with other possible medical causes for elevated amylase levels were excluded. We also compared the clinical and laboratory parameters of hyperamylasemic vs. normoamylasemic hospitalized patients with gastroenteritis. RESULTS: A total of 1041 patients with acute gastroenteritis were identified. Serum amylase levels were determined in 701 patients and were abnormally elevated in 66 of them. In 15 patients, other possible causes of hyperamylasemia were present, and these patients were excluded. The mean serum amylase level among the remaining 51 patients (7.4% of the remaining 686 patients with gastroenteritis) was 1.32 of the upper normal level, with a range of up to 2.2 times the upper normal range. Clinicians tended to admit more hyperamylasemic patients than normoamylasemic patients (10 of 51 vs. 65 of 635; P =.03, 1 sided). However, the course of gastroenteritis in the hospitalized hyperamylasemic patients did not differ significantly from that in the hospitalized normoamylasemic patients, as judged by the clinical signs and symptoms, laboratory results, length of hospital stay, and need for antibiotics. CONCLUSIONS: Gastroenteritis is associated with a mild to moderate elevation of serum amylase levels in a significant portion of patients and should be included in the differential diagnosis of hyperamylasemia. Such elevation, however, does not seem to bear clinical significance in terms of the severity of disease.

Acute Disease↗

Pseudohypoaldosteronism type II: marked sensitivity to thiazides, hypercalciuria, normomagnesemia, and low bone mineral density.

Mutations in WNK kinases cause pseudohypoaldosteronism type II (PHA II) and may represent a novel signaling pathway regulating blood pressure and K(+) and H(+) homeostasis. PHA II is an autosomal dominant disorder characterized by hypertension, hyperkalemia, and metabolic acidosis, with normal glomerular filtration rate. Thiazide diuretics correct all abnormalities. Inactivating mutations in the thiazide-sensitive NaCl cotransporter cause Gitelman syndrome, featuring hypotension, hypokalemia, and metabolic alkalosis plus hypocalciuria and hypomagnesemia. We investigated whether hypercalciuria and hypermagnesemia occurred in a large family with PHA II. Eight affected and eight unaffected members of a PHA II family with the Q565E WNK 4 mutation were studied. In affected members blood and urinary chemistry were measured on and off hydrochlorothiazide (HCTZ), and bone mineral density was determined. Marked sensitivity to HCTZ was found. A mean dose of 20 mg/d reduced mean blood pressure in the six hypertensive subjects by 54.3 (systolic) and 24.5 (diastolic) mm Hg. In affected subjects, HCTZ reduced mean serum K(+) by 1.12 mmol/liter, mean serum Cl(-) by 6.2 mmol/liter, and mean urinary calcium by 65% and elevated mean serum calcium by 0.11 mmol/liter and mean serum urate by 118 micromol/liter. Compared with the literature, this represents an increase of 6-7 in HCTZ potency. Affected members had normomagnesemia, hypercalciuria (336 +/- 113 vs. 155 +/- 39 mg/d in unaffected relatives, P = 0.0002), and decreased bone mineral density. In PHA II the observed marked sensitivity to thiazides and the hypercalciuria are consistent with increased NaCl cotransporter activity. PHA II may serve as a model to investigate thiazides' beneficial effects and side effects.

Adult↗