Spontaneous pneumomediastinum (SP) unrelated to assisted ventilation is a newly recognised complication of severe acute respiratory syndrome (SARS). The objective of the present study was to examine the incidence, risk factors and the outcomes of SP in a cohort of SARS victims from a community outbreak.Data were retrieved from a prospectively collected database of virologically confirmed SARS patients. One hundred and twelve cases were analysable, with 13 patients developing SP (11.6%) at a mean ¡ SD of 19.6 ¡ 4.6 days from symptom onset.Peak lactate dehydrogenase level was associated with the development of SP. SP was associated with increased intubation and a trend towards death. Drainage was required in five cases. For patients who survived, the SP and/or the associated pneumothoraces took a median of 28 days (interquartile range: 15-45 days) to resolve completely.In conclusion, spontaneous pneumomediastinum appeared to be a frequent complication of severe acute respiratory syndrome. Further research is needed to investigate its pathogenesis. Severe acute respiratory syndrome (SARS) has been documented to be caused by a novel coronavirus (SARS-CoV) [1][2][3], which satisfied the Koch's postulations for causation [4,5]. At the time of writing, the numbers of probable SARS cases has reached 8,422 globally [6]. Two previous studies have noted the occurrence of spontaneous pneumomediastinum (SP) occasionally in patients with SARS, unrelated to assisted ventilation [7,8]. However, SP in SARS has not been systematically studied. In the present study the incidence, risk factors and the implications of the development of SP in SARS sufferers were examined.
MethodsThe present study examined SP in SARS patients by retrospective analysis of a prospectively collected SARS database. Patients included in the study were consecutive SARS patients admitted to the United Christian Hospital (Hong Kong, SAR, China) during a community outbreak from March 24 to April 28, 2003. Patients met a modified WHO definition of SARS, which included fever (o38uC), cough or shortness of breath, new pulmonary infiltrates on radiological examination, in the absence of an alternative diagnosis, together with virological documentation of SARS-CoV infection (paired serology and/or positive RT-PCR for SARS-CoV from clinical specimens). All patients were treated with a standard protocol of broad spectrum antibiotics, ribavirin and a tailing regimen of corticosteroids [9]. The clinical, haematological, biochemical, radiological and virological findings were prospectively entered into a preset database, according to previous publications [1,7].Chest radiographs were taken at intervals of 1 to 3 days, depending on clinical need. SP was defined as the presence of gas in the mediastinum, occurring before assisted ventilation. For equivocal cases, high resolution computed tomography (HRCT) of the thorax would be utilised to detect this complication. All chest radiographs and HRCT were interpreted by thoracic radiologists. Results were expressed ...