Case Presentation: A 62 year old male presented with severe recurrent pleural effusions. He has a history of End Stage Renal Disease (ESRD) on hemodialysis (HD), Coronary Artery Disease (CAD), Atrial Septal Defect (ASD) status post repair one month prior to presentation, pericarditis and recurrent pericardial effusion status post pericardial window, and diet-controlled diabetes mellitus type 2.While waiting to undergo an ASD repair at an outside hospital, the patient developed pericarditis and pericardial effusion. He was started on colchicine 0.6mg every other day for 3 months, but then underwent a pericardial window after a recurrence of the pericardial effusion for more definitive management; he ultimately underwent an ASD closure without complications, until he had recurrence of worsening dyspnea at rest. Chest X-ray showed a left sided pleural effusion, with a simple fluid collection. He had a therapeutic thoracentesis, where ~400mL of fluid was removed, resulting in significant symptom improvement and was discharged. Fluid studies showed a transudative pleural effusion. He continued to have recurrence of pleural effusions, which resulted in a VATS decortication.Workup for him included repeat fluid studies, which continued to show a transudate and negative pleural fluid culture, and an echocardiogram which showed only successful ASD closure. Simultaneously, his medications were reviewed, showing he had been on 100mg BID of hydralazine for over two years. Given that there was no other obvious source of his recurrent pericardial and later pleural effusions, an ANA was obtained which was negative. Subsequently anti- histone antibodies was strongly positive, indicating drug induced lupus.
Discussion: Hydralazine Induced Lupus (HILS) occurs in 7-13% of patients taking hydralazine1. Drug induced lupus typically avoids involvement of the renal, pulmonary, or central nervous systems. Pericardial involvement of HILS occurs in less than 5% of patients2. Additionally, most patient’s develop HILS within 3 months of treatment, however, as seen with our patient, it can develop multiple years after initiation(4). Lab findings of HILS typically show positive ANA in >95% of cases, however there have been cases of ANA-negative HILS. Ultimately, though uncommon, HILS should be considered as a diagnosis in patients with pleural effusions or pleural effusions.
Conclusions: Multiple cases and studies have demonstrated that Drug-induced lupus is a side effect of hydralazine5. Incidence of DILS is 5.4% at 100mg daily dose, and 10.4% if at 200mg daily dose of hydralazine. If this patient had been worked up initially, or D-I lupus was included in the differential, he could have been spared multiple surgical interventions (Pericardial window, VATS/pleurodesis/chest tube), however instead he ended up having multiple hospital stays and multiple invasive procedures culminating in the VATS/pleurodesis to resolve this loculated pleural effusion, all resulting from a simple, commonly used medication.