Klinefelter's syndrome associated with progressive muscular atrophy simulating Kennedy's disease

Case report: Klinefelter syndrome may protect against the development of spinal and bulbar muscular atrophy

Spinal and bulbar muscular atrophy (SBMA) is an X-linked recessive motor neuron disease caused by the expansion of cytosine-adenine-guanine (CAG) repeats in the androgen receptor (AR) gene. It is thought that the nuclear translocation of abnormal AR proteins following binding to testosterone triggers the onset of the disease. We report the case of a patient who had SBMA coincident with Klinefelter syndrome. He developed SBMA symptoms rapidly after receiving androgen replacement therapy for Klinefelter syndrome. No cases of coincident SBMA and Klinefelter syndrome have been reported, and if confirmed by further patients in future, that androgen hormones are strongly associated with the development and progression of SBMA in fact in humans.

Total Intravenous Anesthesia in a Malignant Hyperthermia-Susceptible Patient with Klinefelter Syndrome Undergoing Orthognathic Surgery

ABSTRACT

A patient with Klinefelter syndrome and skeletal Class III malocclusion experienced a malignant hyperthermia-like reaction while undergoing orthognathic surgery. The patient fully recovered after prompt diagnosis and management, and surgery was reattempted under total intravenous anesthesia. The patient was discharged without any anesthetic complications and was satisfied with the surgical results. This is the first described case of a malignant hyperthermia-like event in a patient with Klinefelter syndrome. Total intravenous anesthesia may be safely administered in malignant hyperthermia-susceptible patients who require orthognathic surgery.

Clinical manifestations and AR gene mutations in Kennedy's disease

Kennedy's disease, resulted from the expansion of a CAG repeat in exon 1 of androgen receptor (AR) gene, is a motor neuron degenerative disease in the brainstem and spinal cord with the slow development of facial, bulbar, and limb muscle degeneration. To investigate the clinical manifestations and gene mutations in Han Chinese patients with Kennedy's disease. The clinical manifestations of 5 male Han Chinese patients including 2 probands and their relatives from 2 families and 1 sporadic case were retrospectively studied. The CAG repeats in the first exon of AR were screened in 5 Han Chinese people including 2 probands and their healthy relatives from 2 families and 1 sporadic case by polymerase chain reaction (PCR) and direct sequencing. The average age at onset of Kennedy's disease was 48.20 ± 8.70 (mean ± SD) years and the average duration was 7.60 ± 5.32 years. All the patients showed slow onset and progressive weakness, wasting, and fasciculations of the whole body. Four patients demonstrated decreased fertility and 1 patient showed mild gynecomastia. Serum creatine kinase and testosterone levels were elevated mildly in 2 and 1 patients, respectively. The electromyogram showed neurogenic abnormalities. Muscle magnetic resonance demonstrated reduced muscle volume and fatty infiltration. Three different enlarged CAG domains were discovered in the 2 families and 1 sporadic patient with Kennedy's disease, and the CAG repeat number was 48, 43, and 44, respectively. The clinical manifestations of Kennedy's disease in Han Chinese middle-aged men were progressive weakness and atrophy in the bulbar and spinal muscles, occasionally demonstrating incomplete androgen insensitivity syndrome. These patients were also characterized with enlarged CAG repeat number in the first exon of AR, indicating that CAG number could be used in the diagnosis of Han Chinese patients with Kennedy's disease.

Effects of sex chromosome dosage on corpus callosum morphology in supernumerary sex chromosome aneuploidies

Background

Supernumerary sex chromosome aneuploidies (sSCA) are characterized by the presence of one or more additional sex chromosomes in an individual’s karyotype; they affect around 1 in 400 individuals. Although there is high variability, each sSCA subtype has a characteristic set of cognitive and physical phenotypes. Here, we investigated the differences in the morphometry of the human corpus callosum (CC) between sex-matched controls 46,XY (N =99), 46,XX (N =93), and six unique sSCA karyotypes: 47,XYY (N =29), 47,XXY (N =58), 48,XXYY (N =20), 47,XXX (N =30), 48,XXXY (N =5), and 49,XXXXY (N =6).

Methods

We investigated CC morphometry using local and global area, local curvature of the CC boundary, and between-landmark distance analysis (BLDA). We hypothesized that CC morphometry would vary differentially along a proposed spectrum of Y:X chromosome ratio with supernumerary Y karyotypes having the largest CC areas and supernumerary X karyotypes having significantly smaller CC areas. To investigate this, we defined an sSCA spectrum based on a descending Y:X karyotype ratio: 47,XYY, 46,XY, 48,XXYY, 47,XXY, 48,XXXY, 49,XXXXY, 46,XX, 47,XXX. We similarly explored the effects of both X and Y chromosome numbers within sex. Results of shape-based metrics were analyzed using permutation tests consisting of 5,000 iterations.

Results

Several subregional areas, local curvature, and BLDs differed between groups.

Moderate associations were found between area and curvature in relation to the spectrum and X and Y chromosome counts. BLD was strongly associated with X chromosome count in both male and female groups.

Conclusions

Our results suggest that X- and Y-linked genes have differential effects on CC morphometry. To our knowledge, this is the first study to compare CC morphometry across these extremely rare groups.