[Extremely severe pulmonary lymphangioleiomyomatosis with combined brain, liver, kidney, and lung involvement: a case report].

We reported a case of extremely severe tuberous sclerosis complex-associated lymphangioleiomyomatosis (TSC-LAM) involving the brain, liver, kidneys, and lungs that was successfully treated with sirolimus, with a complete 17-year follow-up. The patient was diagnosed in 2008 and experienced rapid progression; by 2012, the patient had developed respiratory failure, severe anemia, renal insufficiency, and extreme abdominal distension. After 3 days of treatment with sirolimus, the aforementioned symptoms improved significantly, and respiratory failure resovled. Over the following 7 years of regular maintenance therapy, lung function declined only slightly each year, and the 6-minute walking test(6MWT) showed no decline. However, after sirolimus was discontinued from January 2020 to April 2021, the patient's lung function and 6MWT declined rapidly, with concurrent development of pneumothorax. Although sirolimus was subsequently resumed and remained effective, with no recurrence of pneumothorax or chylothorax, parameters such as lung function and 6MWT still did not recover significantly. This case suggests that TSC-LAM requires long-term maintenance therapy with sirolimus. Abrupt discontinuation of treatment may lead to rapid clinical deterioration.