Expanding the clinical and molecular spectrum of lethal congenital contracture syndrome 8 associated with biallelic variants of ADCY6.

Arthrogryposis multiplex congenita (AMC) is defined as congenital, non-progressive contractures in more than two joints and in multiple body areas, resulting from reduced fetal mobility. So far, more than 400 causative genes for AMC have been identified. Some isolated AMC phenotypes arise as a result of mutations in genes encoding components required for motor neuron structure, function, and myelination, as in the case of ADCY6 encoding the enzyme adenylyl cyclase type 6. ADCY6 inactivation, due to biallelic variants, have been previously associated with the lethal congenital contracture syndrome 8 (LCCS8). So far, only four LCCS8 patients, from two families, have been reported. Here, we describe a new patient affected by a severe form of AMC, harboring two novel compound heterozygous variants in ADCY6. Our findings expand the clinical and mutational spectrum of LCCS8, showing a possible correlation between the impact of the ADCY6 missense variants reported to date, predicted by molecular modeling, and the severity of the phenotype.

All You Need Is Evidence: What We Know About Pneumonia in Children With Neuromuscular Diseases.

Neuromuscular diseases may involve all major respiratory muscles groups including inspiratory, expiratory, and bulbar muscles. Respiratory complications are the major cause of morbidity and mortality. Pneumonia represents a frequent cause of morbidity in children with neuromuscular disease. The aim of this review is to collect knowledge about pneumonia in children with neuromuscular diseases. Pneumonia usually follows viral respiratory infections of the upper respiratory tract, due to the combination of an increased amount of nasal and oral secretions and an impairment of the cough efficiency and of the clearance of secretions due to the muscle weakness, further compromised by the infection itself. The accumulation of bronchial secretions leads to atelectasis and promote bacterial infection. Moreover, dysfunction of swallowing mechanism exposes these children to the risk of developing aspiration pneumonia. However, etiology of viral and bacterial respiratory infection in these patients is still poorly studied.