Objective: The goal of this study was to analyze the factors that have an impact on morbidity and mortality in patients with myelomeningocele (MMC).
Methods: A retrospective cohort study was conducted to analyze factors associated with MMC that influence the morbidity and mortality of the disease. Data were collected from medical records of children who underwent the primary repair of MMC at the Fernandes Figueira Institute-Oswaldo Cruz Foundation (IFF-Fiocruz) between January 1995 and January 2015, with a minimum follow-up of 1 year. The following variables were analyzed: demographic characteristics (gestational age, sex, and birth weight); clinical features (head circumference at birth, anatomical and functional levels of MMC, hydrocephalus, symptomatic Chiari malformation type II, neurogenic bladder, and urinary tract infection [UTI]); and surgical details such as timing of repair of MMC, age at first shunt placement, shunt surgery modality (elective or emergency), concurrent surgery (correction of MMC and shunt insertion in the same surgical procedure), incidence and cause of shunt dysfunction, use of external ventricular drain, transfontanelle puncture, surgical wound complications prior to shunting, and endoscopic treatment of hydrocephalus.
Results: A total of 231 patients with MMC were included in the analysis. Patients were followed for periods ranging from 1 to 20 years, with a mean of 6.9 years. The frequency of shunt placement was observed mainly among patients with MMC at the highest spinal levels (p < 0.01). The main causes of morbidity and mortality in patients with MMC were shunt failures, diagnosed in 91 of 193 cases (47.2%) of hydrocephalus, and repeated UTIs, in 129 of 231 cases (55.8%) of MMC; these were the main causes of hospitalization and death. Head circumference ≥ 38 cm at birth was found to be a significant risk factor for shunt revision (p < 0.001; 95% CI 1.092-1.354). Also, the lumbar functional level of MMC was associated with less revision than upper levels (p < 0.014; 95% CI 0.143-0.805). There was a significant association between recurrent UTI and thoracic functional level.
Conclusions: Macrocephaly at birth and higher levels of the defect have an impact on worse outcome and, therefore, are a challenge to the daily practice of pediatric neurosurgery.
Keywords: CM-II = Chiari malformation type II; Chiari malformation type II; ETV = endoscopic third ventriculostomy; IFF-Fiocruz = Fernandes Figueira Institute–Oswaldo Cruz Foundation; MMC = myelomeningocele; NTD = neural tube defect; PFD = posterior fossa decompression; UTI = urinary tract infection; cerebrospinal fluid shunt; hydrocephalus; myelomeningocele; spinal dysraphism.