Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) Is usually idiopathic but can be  associated with systemic autoimmune diseases. Mixed connective tissue disease (MCTD), characterized by anti-U1RNP positivity, has only rarely been reported in association with CIDP. 

We present a case of CIDP associated with (MCTD) that demonstrated atypical features, including multiple cranial nerve sensory motor involvement (3,4,5, 6,7,9,10), atypical pattern of sensory loss and upper limb onset, suggesting a distinct pathophysiological mechanism compared to idiopathic CIDP. Despite this unusual presentation, the therapeutic response to corticosteroids was comparable to other forms of CIDP. Importantly, management strategy in such cases is also unique as it  requires recognition and treatment of the underlying connective tissue disorder, which significantly impacts long-term outcomes.

A 29-year-old woman  with 5 month history of bilateral  upper limb weakness and paresthesia progressing  to involve both lower limbs and further development of dysphagia, diplopia and facial numbness, with a previous  3-year history of Raynaud’s phenomenon, inflammatory polyarthritis with morning stiffness, digital ulcer progressing to gangrene, and photosensitive facial rash.Examination revealed malar hyperpigmentation, prior digital amputation, bilateral ophthalmoparesis, left trigeminal sensory loss, bilateral LMN left facial palsy, palatal weakness with uvular deviation, generalized hypotonia with quadriparesis, atypical distribution of   sensory loss including the limbs and neck.Nerve conduction studies showed demyelination with conduction block, and CSF revealed albuminocytologic dissociation. Autoimmune evaluation confirmed anti-U1RNP positivity with systemic features consistent with MCTD as per Alarcon Segovia criteria. The patient improved with corticosteroid therapy .