Klein J M, Thompson M W, Snyder J M, George T N, Whitsett J A, Bell E F, McCray P B, Nogee L M
Department of Pediatrics, University of Iowa, Iowa City 52242-1083, USA.
J Pediatr. 1998 Feb;132(2):244-8. doi: 10.1016/s0022-3476(98)70439-1.
A 38-day-old male infant with persistent pulmonary hypertension and respiratory failure since birth was found to have a complete absence of surfactant protein B (SP-B) along with an aberrant form of SP-C in his tracheal aspirate fluid, findings consistent with the diagnosis of hereditary SP-B deficiency. Surprisingly, SP-B and SP-B messenger ribonucleic acid were present in lung biopsy tissue. However, DNA sequence analysis demonstrated a point mutation in exon 5 of one of the SP-B gene alleles. The infant's mother was found to be a carrier of this mutation. The infant's other SP-B allele did not differ from the published DNA sequence for the SP-B gene. We conclude that this patient had a transient deficiency of SP-B, in contrast to that of previously described infants with irreversible respiratory failure caused by hereditary SP-B deficiency. We recommend that infants with suspected SP-B deficiency have serial analysis of tracheal fluid samples for both SP-B and SP-C before lung biopsy, along with genetic analysis for the known SP-B mutations. We speculate that the new mutation found in one of this patient's SP-B genes was in part responsible for the transient deficiency of SP-B.
一名38日龄男婴自出生起就患有持续性肺动脉高压和呼吸衰竭，其气管吸出液中发现完全缺乏表面活性物质蛋白B（SP-B）以及一种异常形式的SP-C，这些发现符合遗传性SP-B缺乏症的诊断。令人惊讶的是，肺活检组织中存在SP-B和SP-B信使核糖核酸。然而，DNA序列分析显示SP-B基因的一个等位基因的外显子5存在点突变。发现该婴儿的母亲是这种突变的携带者。该婴儿的另一个SP-B等位基因与已公布的SP-B基因DNA序列没有差异。我们得出结论，与先前描述的因遗传性SP-B缺乏导致不可逆呼吸衰竭的婴儿不同，该患者存在SP-B的短暂缺乏。我们建议，对于疑似SP-B缺乏的婴儿，在进行肺活检前，应对气管液样本进行SP-B和SP-C的系列分析，并对已知的SP-B突变进行基因分析。我们推测，在该患者的一个SP-B基因中发现的新突变部分导致了SP-B的短暂缺乏。
