Israel Medical Association Journal

Children affected with Poland syndrome are born with missing or underdeveloped muscles (typically pectoralis major) on one side of the body. Breast abnormalities such as unilateral hypoplasia or agenesis of the breast and nipple may also occur. Other muscles on the affected side, including other muscles in the chest wall, shoulder, arm, and hand, may be missing or underdeveloped [1]. Ribs may be noticeable due to the loss of subcutaneous fat. Sparse or absent axillary and pectoral hairs are a common manifestation of this syndrome.

Background: Statin-induced myalgia is defined as muscle pain without elevation of serum creatine phosphokinase levels and is a well-known complaint among statin users. Chronic pain syndromes affect a high percentage of the population. These pain syndromes may confound the reports of statin-induced myalgia.

Objectives: To compare the occurrence of chronic pain among patients on statin therapy who developed myalgia with those who did not.

Methods: This study included 112 statin-treated patients, who were followed at the lipid center at Sheba Medical Center. Fifty-six patients had a diagnosis of statin-associated muscle symptoms (SAMS) and 56 did not. Verified questionnaires were used to assess the diagnoses of fibromyalgia, pain intensity, functional impairment, anxiety, and depression in the study population.

Results: Patients with statin myalgia were more likely to fulfil the diagnostic criteria for fibromyalgia than patients without statin myalgia (11 [19.6%] vs. 0, respectively). Patients in the SAMS group exhibited higher levels of anxiety and depression compared with the control group. Female sex, higher scores on the Brief Pain Inventory pain intensity scale, and a Hamilton rating scale level indicative of an anxiety disorder were found to be significant predictors for fibromyalgia in patients presenting with statin myalgia.

Conclusions: A significant percentage of patients diagnosed with statin myalgia fulfilled the diagnostic criteria for fibromyalgia depression or anxiety disorder. Detection of these patients and treatment of their primary pain disorders or psychiatric illnesses has the potential to prevent unnecessary cessation of effective statin therapy.

Objectives: To determine if low plasma vitamin D level is a risk factor for MAEs in statin users.

Methods: Plasma levels of 25(OH) vitamin D were measured as part of the routine evaluation of unselected statin-treated patients attending the coronary and lipid clinics at our hospital during the period 2007–2010. Medical data on muscle complaints and statin use were retrieved from the medical files. Creatine kinase (CK) levels were derived from the hospital laboratory database.

Results: The sample included 272 patients (141 men) aged 33–89 years. Mean vitamin D level was 48.04 nmol/L. Levels were higher in men (51.0 ± 20.5 vs. 44.7 ± 18.9 nmol/L, P = 0.001) and were unaffected by age. MAEs were observed in 106 patients (39%): myalgia in 95 (35%) and CK elevation in 20 (7%); 11 patients (4%) had both. There was no difference in plasma vitamin D levels between patients with and without myalgia (46.3 ± 17.7 vs. 48.9 ± 21.0 nmol/L, P = 0.31), with and without CK elevation (50.2 ± 14.6 vs. 47.8 ± 20.3 nmol/L, P = 0.60), or with or without any MAE (50.4 ± 15.0 vs. 47.8 ± 10.2 nmol/L, P = 0.27). These findings were consistent when analyzed by patient gender and presence/absence of coronary artery disease, and when using a lower vitamin D cutoff (< 25 nmol/L).

Conclusions: There is apparently no relationship between plasma vitamin D level and risk of MAEs in statin users.

Background: Myotonic dystrophy type 2 (DM2) is an autosomal dominant, multisystem disorder caused by a CCTG tetranucleotide repeat expansion located in intron 1 of the zinc finger protein 9 gene (ZNF9 gene) on chromosome 3q 21.3.

Objectives: To describe the clinical, electrophysiologic and pathologic findings in patients with myotonic dystrophy 2.

Methods: We evaluated 10 patients genetically, clinically and electrophysiologically during the years 2007 to 2008.

Results: All patients were of Jewish European ancestry. Among affected individuals, eight patients had symptoms of proximal muscle weakness, two had muscle pain, and two exhibited myotonia. On physical examination six patients had severe weakness of hip flexor muscles. Seven individuals underwent cataract surgery, and cardiac involvement was seen in one case. On the initial electromyographic (EMG) examination five patients demonstrated myotonic discharges; repeated studies showed these discharges in nine cases. Six muscle biopsies showed non-specific pathological changes. Seven patients had an affected first-degree relative with either a diagnosed or an undiagnosed muscular disorder, consistent with an autosomal dominant trait.

Conclusions: DM2 may often present with proximal muscle weakness without myotonia. EMG may initially fail to show myotonic discharges, but these discharges may eventually show in most cases on repeated EMG. Thus, DM2 may be underdiagnosed and should be included in the differential diagnosis of adult patients of Jewish European ancestry presenting with proximal lower limb weakness.
 

Background: Common peroneal neuropathies, usually located at the fibular head, are one of the causes of drop foot, a condition often evaluated in the electromyography laboratory.

Objectives: To study the motor conduction properties of the common peroneal nerve and its branches of distribution in patients with paralyzed drop foot, several weeks after their first stroke, assuming that its inversion position can cause neuropathy around the fibular neck.

Methods: We performed peroneal nerve conduction study on 76 legs of 38 patients, 12–73 days after their first stroke. All the patients had flaccid drop foot on the involved side. The stimulating electrode was placed at the postero-lateral aspect of the fibular neck. Motor nerve conduction latency and compound muscle action potential amplitude were measured along the proximal part of the deep and the superficial peroneal nerve, comparing the paralyzed to the sound leg. Paired sample t-test and paired t-test were used to compare the nerve conduction properties between the sound and the paralytic leg. The linear liaison between the two legs was determined by Pearson coefficient and the test based on it.

Results: The differences between motor conduction latencies and between CMAP[1] amplitudes, comparing the paralyzed to the sound side, recorded in both the deep peroneal nerve and the superficial peroneal nerve, were statistically significant (P < 0.05).
Conclusions: It seems that the permanent equino-varus position of the paralyzed foot might affect common peroneal nerve conduction properties at the level of the fibular neck by demyelination, axonopathy, or both. Possible reasons for these pathological changes are nerve traction or nerve compression, but temperature changes in the paralytic leg should also be considered. Ankle-foot orthoses can be prescribed for prevention or correction of deformities of the foot and ankle and reduction of the weight-bearing forces

Background: Ion Channel Innovations has developed a gene transfer product, ftMaxi-K, and has begun clinical trials to investigate the effect of increased expression of Maxi-K channels in the smooth muscle of the penis or bladder in patients with erectile dysfunction and those with overactive bladder. The primary function of K channels is to modulate Ca⁺⁺ influx through Ca-channels (i.e., L-type, voltage-dependent). The amount of Ca⁺⁺ that enters the cell through these channels is a major determinant of the free intracellular calcium levels inside the smooth muscle cell, which in turn determines the degree of smooth muscle cell contraction. Increased Maxi-K channel activity is associated with smooth muscle cell relaxation, resulting in, for example, penile erection and detrussor muscle relaxation. A phase I clinical trial that used dMaxi-K has been completed and a similar trial to assess safety of the transfer for overactive bladder is about to begin.

Objectives: To assess the safety and tolerability of escalating dMaxi-K doses by clinical evaluations and laboratory tests, and to measure efficacy objectives by means of the International Index of Erectile Function scale.

Methods: In the erectile dysfunction trial 11 patients with moderate to severe erectile dysfunction were given a single-dose corpus cavernosum injection of dMaxi-K, a "naked" DMA plasmid carrying the human cDNA encoding for the gene for the a, or pore-forming, subunit of the human smooth muscle Maxi-K channel, hSIo. Three patients each were given 500,1000, and 5000 pg and two patients were given 7500 pg doses of ftMaxi-K and followed for 24 weeks. Patient responses were validated by partner responses.

Results: There were no serious adverse events and no dose-related adverse events attributed to gene transfer for any patient at any dose or study visit. No clinically significant changes from baseline were seen in physical evaluations (general and genitourinary), hematology, chemistry and hormone analyses, or in cardiac events evaluated by repeated electrocardiograms. Importantly, no plasmid was detected in the semen of patients at any time after the injections. Patients given the two highest doses of dMaxi-K had apparent sustained improvements in erectile function as indicated by improved IIEF-EF domain scores over the length of the study. One patient given 5000 (jg and one given 7500 [jg reported EF category improvements that were highly clinically significant and were also maintained through the 24 weeks of study.
Conclusions: Efficacy conclusions cannot be drawn from results of a phase 1 trial with no control group. However, the promising primary safety outcomes of the study and preliminary indications of effectiveness provide evidence that ftMaxi-K gene transfer is a viable approach to the treatment of erectile dysfunction and other smooth muscle diseases with targeted access

Background: Persistent creatine kinase elevation is occasionally encountered in subjects without any clinical manifestation of a neuromuscular disorder or any condition known to be associated with increased serum CK[1] levels. It is still unresolved whether extensive investigations and specifically a muscle biopsy should be performed in clinically normal individuals with elevated CK levels.

Objective: To study the muscle pathology of patients with asymptomatic or minimally symptomatic hyperCKemia.

Methods: The clinical and laboratory data of patients with persistent hyperCKemia and normal neurologic examination were reviewed and their muscle biopsies evaluated.

Results: The study group included 40 patients aged 7–67 years; the male to female ratio was 3:1. Nineteen patients were completely asymptomatic, 20 had mild non-specific myalgia, and 1 had muscle cramps. Electromyography was performed in 27 patients and showed myopathic changes in 7 (26%). Abnormal muscle biopsy findings (e.g., increased variation in fiber size, increased number of central nuclei and occasional degenerating fibers) were detected in 22 of the 40 patients (55%). No fat or glycogen accumulation was detected. Immunohistochemistry demonstrated abnormal dystrophin staining in 3 patients (8%), resembling the pathologic changes of Becker muscular dystrophy. No abnormal findings were detected on immunohistochemical staining for merosin, dysferlin, caveolin 3, or alpha and gamma sarcoglycans. The EMG[2] findings did not correlate with the pathologic findings.

Conclusions: Abnormal muscle biopsies were found in 55% of patients with asymptomatic or minimally symptomatic hyperCKemia. Specific diagnosis of muscular dystrophy, however, was possible in only 8% of the patients.