New diagnosis and subsequent post-partum radiological improvement of lymphangioleiomyomatosis.

A 39-year-old nulliparous woman became breathless after a caesarean section. CT pulmonary angiography (fig 1) showed no filling defect but cysts, small bilateral effusions and thickened interlobular septa were visible consistent with a possible diagnosis of lymphangioleiomyomatosis (LAM). An open lung biopsy performed 11 months later showed that the lung parenchyma contained scattered cysts of various sizes with proliferative smooth muscle bundles in the cyst walls staining for smooth muscle actin and HMB45, which confirmed a diagnosis of LAM. It is thought that the interstitial infiltrates were secondary to LAM. Cardiac failure may have a similar CT appearance, but the patient had no risk factors apart from recent pregnancy, improved with no anti-failure medication and did not have lung crepitations when auscultated in the immediate postoperative period. A follow-up CT scan of the thorax 14 months later (fig 2) showed that the reticular shadowing and pleural effusions had disappeared.