Renal dysfunction can occur in advanced-stage Duchenne muscular dystrophy.

INTRODUCTION: With improved treatments, patients with Duchenne muscular dystrophy (DMD) can survive far beyond adolescence. However, advanced-stage DMD patients are at risk of developing renal dysfunction. In this study, long-term renal function outcomes and associated risk factors in advanced stage DMD were analyzed. METHODS: Fifty-one patients were classified into three different age groups (<20, 20-29, and ≥30 years of age), and cystatin C (CysC) levels were compared among groups. RESULTS: Median serum CysC levels were 0.74 mg/L, 0.63 mg/L, and 0.76 mg/L in the age groups of <20, 20-29, and ≥30 years, respectively (P = .003). Five of the nine patients in the ≥30 years age group showed elevated serum CysC and decreased cardiac function compared with the other four in the group (P = .014). DISCUSSION: Our results indicate an association between cardiac and renal dysfunction in patients with advanced-stage DMD.

Clinical course in a patient with myopathic VLCAD deficiency during pregnancy with an affected baby.

Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is an autosomal recessive mitochondrial fatty acid oxidation disorder that manifests in three clinical forms: (a) severe, (b) milder, and (c) myopathic. Patients with the myopathic form present intermittent muscular symptoms such as myalgia, muscle weakness, and rhabdomyolysis during adolescence or adulthood. Here, the clinical symptoms and serum creatine kinase (CK) levels of a pregnant 31-year-old woman with the myopathic form of VLCAD deficiency were reduced during pregnancy. Clinical symptoms rarely appeared during pregnancy, although she had sometimes suffered from muscular symptoms before pregnancy. When ritodrine was administered for threatened premature labor at 35 weeks of gestation, her CK level was elevated to over 3900 IU/L. She delivered a full-term baby via cesarean section but suffered from muscle weakness with elevated CK levels soon after delivery. It has been reported that an unaffected placenta and fetus can improve maternal ß-oxidation during pregnancy. However, in our case, the baby was also affected by VLCAD deficiency. These suggest that the clinical symptoms of a woman with VLCAD deficiency might be reduced during pregnancy even if the fetus is affected with VLCAD deficiency.

Carnitine deficiency: Risk factors and incidence in children with epilepsy.

BACKGROUND: Carnitine deficiency is relatively common in epilepsy; risk factors reportedly include combination antiepileptic drug (AED) therapy with valproic acid (VPA), young age, intellectual disability, diet and enteral or parenteral feeding. Few studies have examined the correlation between each risk factor and carnitine deficiency in children with epilepsy. We examined the influence of these risk factors on carnitine deficiency, and identified a formula to estimate plasma free carnitine concentration in children with epilepsy. METHODS: Sixty-five children with epilepsy and 26 age-matched controls were enrolled. Plasma carnitine concentrations were measured using an enzyme cycling assay, and correlations were sought with patients' other clinical characteristics. RESULTS: Carnitine deficiency was found in approximately 17% of patients with epilepsy and was significantly associated with carnitine-free enteral formula only by tube feeding, number of AEDs taken (independent of VPA use), body weight (BW), body height and Gross Motor Function Classification System (GMFCS) score. Stepwise multiple linear regression analysis indicated that carnitine concentration (in µmol/L) could be accurately estimated from a formula that does not require blood testing: 42.44+0.14×(BW in kg)-18.16×(feeding)-3.19×(number of AEDs), where feeding was allocated a score of 1 for carnitine-free enteral formula only by tube feeding and 0 for taking food orally (R(2)=0.504, P<0.001). CONCLUSIONS: Carnitine-free enteral formula only by tube feeding, multiple AED treatment and low BW are risk factors for carnitine deficiency in children with epilepsy. l-carnitine should be administered to children at risk of deficiency to avoid complications. Treatment decisions can be informed using an estimation formula that does not require blood tests.

Skin temperature responses to cold stress in patients with severe motor and intellectual disabilities.

Patients with severe motor and intellectual disabilities (SMID) often suffer from autonomic nervous system disturbances. At the same time, the caregivers of patients with SMID face challenges to understand the patients' chronic health problems effectively by simply observing them. Therefore, recognizing specific symptoms is important to improve support for SMID. We investigated the autonomic nervous function in patients with SMID with skin vasomotor responses to cold stimuli. The relationship of the results of cold stress and autonomic symptoms observed by the main caretakers was also examined. We analyzed 38 patients with SMID. Their hand skin temperature was measured before and after cold stimuli using infrared thermography. A 'distal-dorsal difference' (DDD) at baseline, and the recovery rate of the second fingertip and dorsum were calculated. All main caregivers filled out questionnaires evaluating autonomic symptoms. The recovery rate of the second fingertip and dorsum after cold stimuli was lower than 80% in 64% and 60% patients, respectively. The baseline DDD was greater than 1 °C in 84% of the patients. A DDD>1 °C was associated with a reduced recovery rate. All caregivers recognized some autonomic-related symptoms. Patients with constipation or snoring demonstrated a reduced recovery rate. However, none of the observed symptoms can predict the presence of a reduced rate with cold stimuli in a statistically significant way. This study showed excessive sympathetic nerve activities in patients with SMID. The baseline DDD could be a valuable parameter accessing their microvascular circulation. To improve the life of a person with SMID, accessing autonomic function using a noninvasive method, such as thermography is warranted without directly observed symptoms.