# Three‐Year Diagnostic Delay in Shrinking Lung Syndrome: Rituximab‐Theophylline Combination as Rescue Therapy

## TL;DR

A woman with lupus had undiagnosed lung issues for three years before being correctly diagnosed with shrinking lung syndrome and successfully treated with a combination of drugs.

## Contribution

Reports a successful rescue therapy using rituximab, prednisolone, and theophylline for a rare lupus complication.

## Key findings

- A 41-year-old woman with SLE was diagnosed with SLS after a 3-year delay.
- Combination therapy improved pulmonary function and symptoms in the patient.
- Delayed diagnosis of SLS in SLE patients may increase morbidity.

## Abstract

Shrinking lung syndrome (SLS) is an infrequent complication of systemic lupus erythematosus (SLE). A 41‐year‐old woman with a 10‐year history of SLE presented with dyspnea, chest pain, and dry cough. She had poor medication compliance and multiple hospitalizations over 3 years for similar symptoms, without a definitive diagnosis. Imaging revealed bilateral basal atelectasis and an elevated right hemidiaphragm, while pulmonary function tests (PFTs) showed a restrictive pattern. Other lung and cardiac conditions were excluded, leading to a diagnosis of SLS. Treatment with rituximab, prednisolone, and theophylline improved PFTs, chest pain, cough, and dyspnea at follow‐up. Clinicians should consider SLS in SLE patients with dyspnea and characteristic imaging, as delayed diagnosis may increase morbidity.

This report presents a case of systemic lupus erythematosus with multiple hospitalizations over 3 years due to unexplained respiratory symptoms (dyspnea, reduced lung volume, elevated diaphragm, coughing, and chest pain), ultimately diagnosed with shrinking lung syndrome (a rare complication of lupus without established treatment) and successfully treated with rituximab, prednisolone, and theophylline.