In the intricate landscape of autoimmune disorders, Systemic Lupus Erythematosus (SLE) and sarcoidosis stand out, each presenting its unique set of challenges. Neuropsychiatric Systemic Lupus Erythematosus (NPSLE) is a well-known complication, occurring in a significant portion of SLE cases, while sarcoidosis, though rare, manifests with distinct clinical features. Coexisting NPSLE and sarcoidosis, although exceptionally uncommon, present a diagnostic dilemma.

We present the case of a 45-year-old man, previously diagnosed with sarcoidosis, who presented with perplexing symptoms - double vision, muscle weakness, and sensory deficits. The clinical puzzle deepened when bilateral sixth cranial nerve neuropathies and polyneuropathy were observed. Laboratory investigations revealed intriguing findings, including positive antinuclear antibodies, Coombs-positive hemolytic anemia, and proteinuria. Imaging studies indicated active sarcoidosis alongside NPSLE.

Navigating through this diagnostic maze, we were faced with various potential diagnoses, including sarcoidosis exacerbation, chronic inflammatory demyelinating polyneuropathy, and paraneoplastic syndrome. Cranial neuropathies, relatively rare in both conditions, further complicated the diagnosis. The presence of interstitial lung disease and bilateral hilar lymphadenopathy, typically indicative of sarcoidosis, raised suspicions in the context of SLE.

Management involved a delicate balance of symptomatic treatments and immunosuppressants (intravenous Cyclophosphamide), emphasizing the importance of tailored therapeutic approaches. Genetic predispositions, notably HLA-B8-DR3, hinted at the shared genetic subfloor of these disorders.

In conclusion, this case underscores the intricacies involved in diagnosing the coexistence of NPSLE and sarcoidosis. Precise diagnostic tools, in-depth understanding, and comprehensive research are imperative to unravel the mysteries surrounding these rare concurrent autoimmune conditions.

Bishal Kunwor is a dedicated medical student currently in his fourth year of study, pursuing the Bachelor of Medicine and Bachelor of Surgery (MBBS) program at Nepalese Army Institute of Health Sciences, Tribhuvan University. He has exhibited exceptional academic prowess, being awarded a full scholarship through a competitive examination conducted by the Ministry of Education, Nepal.

In his nascent journey in the realm of medical research, Kunwor has displayed promising potential. He has authored and co-authored two published reports, showcasing his commitment to advancing medical knowledge. Furthermore, he has contributed significantly to the academic community by submitting several articles, eagerly awaiting publication.