Maternal contamination at fetal muscle biopsy

Duchenne muscular dystrophy (DMD) can be diagnosed by fetal muscle biopsy a nd immunohistochemical staining showing the absence of dystrophin. We repor t a case of fetal muscle biopsy in which the needle gun was successfully fi red within the fetal gluteal muscle but the sample was cont aminated by mat ernal tissue. This was attributed to the design of the biopsy needle, allow ing transient opening of the biopsy core as the needle penetrated the mater nal rectus sheath, muscle, and myometrium, Histology showed tissue suggesti ve of maternal origin, confirmed by DNA analysis, Repeat sampling revealed fetal muscle with normal dystrophin expression. We recommend that care be t aken during needle insertion to avoid maternal contamination, and tests be used to confirm the fetal source of the sample. Copyright (C) 2000 S. Karge r AG, Basel.