Augusto J-F, Sayegh J, Malinge M-C, Illouz F, Subra J-F, Ducluzeau P-H
Service de Néphrologie-Dialyse-Transplantation, Centre Hospitalier et Universitaire Angers, Université Angers, UPRES EA 3863, Angers, France.
Clin Nephrol. 2008 Apr;69(4):302-5. doi: 10.5414/cnp69302.
Cystic fibrosis (CF) is usually diagnosed during childhood by respiratory or gastro-intestinal symptoms. Hyponatremic hypochloremic dehydration with metabolic alkalosis is a rare but typical presentation of CF in infants. In contrast, only 3 cases have been described in adults. We report a case of CF in a 33-year-old Caucasian female presenting with a severe sodium and chloride depletion caused by inappropriate sweating. She experienced three episodes of severe dehydration before the diagnosis was suspected. Sweat chloride test was pathological and mild pulmonary involvement was found on CT scan. Delta F508 mutation and a rare mutation (3849+40 A/G) on the intron 19 of CFTR gene were found. Interestingly, our patient has a heterozygote twin sister, carrier of the same mutations of CFTR gene who also developed CF but with a different phenotype. We suspect modifier genes to be implicated in the differences observed between the two phenotypes. We discuss the physiopathology of electrolyte disturbance and review the other similar adults cases.
囊性纤维化（CF）通常在儿童期通过呼吸道或胃肠道症状被诊断出来。低钠低氯性脱水伴代谢性碱中毒是婴儿期CF的一种罕见但典型的表现。相比之下，成人中仅报道过3例。我们报告了一例33岁的白种女性囊性纤维化病例，该患者因不适当出汗导致严重的钠和氯缺乏。在怀疑诊断之前，她经历了三次严重脱水发作。汗液氯化物试验呈病理性，CT扫描发现轻度肺部受累。在CFTR基因的第19内含子上发现了ΔF508突变和一种罕见突变（3849 + 40 A/G）。有趣的是，我们的患者有一个杂合子双胞胎姐妹，也是CFTR基因相同突变的携带者，她也患了CF，但表现型不同。我们怀疑修饰基因与观察到的两种表现型之间的差异有关。我们讨论了电解质紊乱的生理病理学，并回顾了其他类似的成人病例。
