Meconium thorax observed in a Chinese neonate with cystic
fibrosis
To the Editor,
A full-term male neonate was delivered by emergency cesarean section
after the discovery of bilateral pleural effusion at 40 weeks of
gestation. Clinical examination revealed general edema, abdominal
distension and liver palpated 4cm under the rib. Radiographic and
ultrasonographic results showed bilateral pleural effusion and ascites
without calcification. Thoracentesis was performed on day 1 of life.
Meconium-like turbid and sticky fluid (Figure 1D) was drained from the
pleural cavity. Cytologic examination showed a large amount of white
blood cells. In addition, squamous epithelial cells (Figure 1A, 1C),
heme crystal (Figure 1B) and old red blood cells were also observed,
indicating the possible existence of perforation of the gut and
diaphragmatic defect. The baby underwent an exploratory laparotomy on
day 2. Perforation of the sigmoid colon was identified and defunctioning
ileostomy was performed. However, owing to the liver enlargement, no
obvious diaphragmatic defects were observed. Postlaparotomy period was
basically uneventful. He was discharged in a good general condition 23
days after birth. Nevertheless, on day 33 of life, the baby was
re-admitted presenting with difficulty in breathing and poor response.
Radiographs revealed severe pneumonia and marked elevation of bilateral
diaphragm, so left and right diaphragmatic exploration by thoracoscope
was performed successively on day 49 and day 55. A posterolateral
hernial sac (defect area: 3×3 cm) was identified in the left diaphragm
and most of the right diaphragm was missing (defect area: 5×4 cm). So,
the adhesions were divided; pyothorax was cleared; the herniated organs
were repositioned into the abdomen and the diaphragm defects were
repaired. After the operation, the baby became clinically stable and was
discharged home on day 73 of life. Whole exome sequencing revealed that
the baby carried two heterozygous mutations in the cystic fibrosis
transmembrane conductance regulator (CFTR) gene. One is c.1210-11T≻G
located in intron 9 (paternal, pathogenic) and the other is c.283 A≻G
(p.L95E) located in exon 4 (maternal, possibly pathogenic). Considering
his manifestations, the baby was finally diagnosed with cystic fibrosis
(CF).
CF is considered a rare disease among the non-Caucasian population. The
clinical phenotypes and genotypic spectrum of Chinese CF patients are
reported to be different from that observed in
Caucasians(1). Our patient carried
compound heterozygous mutations which are not included in the Caucasian
CFTR common mutation-screening panel and have not been reported yet.
CFTR dysfunction causes a spectrum of diseases, with a range in the
number of organs involved and varying disease severity. Typical
phenotypic features of CF include respiratory diseases (bronchiectasis
with persistent airway-based infection and inflammation),
gastrointestinal diseases (meconium ileus (MI)), hepatobiliary
manifestations (pancreatic insufficiency), and male
infertility(2). Our patient presented
severe manifestations, namely colonic perforation, meconium thorax,
severe pneumonia, diaphragmatic defects-caused marked diaphragm
elevation and respiratory failure. It’s difficult to ascertain whether
the diaphragmatic defects in our patient is related to CF. MI is often
the first manifestation of CF and occurs in approximately 20% of CF
patients. CF should therefore be high in the differential diagnosis of
any infant presenting with MI(3).