Misdiagnosis and diagnostic delay in non-paraneoplastic sensory neuronopathies

Abstract

Sensory neuronopathy (SN) is characterized by primary dorsal root ganglia damage and typically manifests as sensory ataxia with multifocal non-length-dependent sensory deficits 1,2 . First described in 1948 by Dr. Derek Denny-Brown 3 , the full phenotypic spectrum and the identification of all SN-related disorders are still pursued 4 . In a way rarely seen ABSTRACT Sensory neuronopathies (SN) are a group of peripheral nerve disorders characterized by multifocal non-length-dependent sensory deficits and sensory ataxia. Its recognition is essential not only for proper management but also to guide the etiological investigation. The uncommon SN clinical picture and its rarity set the conditions for the misdiagnosis and the diagnostic delay, especially in non-paraneoplastic SN. Therefore, our objectives were to characterize the diagnostic odyssey for non-paraneoplastic SN patients, as well as to identify possible associated factors. Methods: We consecutively enrolled 48 non-paraneoplastic SN patients followed in a tertiary neuromuscular clinic at the University of Campinas (Brazil). All patients were instructed to retrieve their previous medical records, and we collected the data regarding demographics, disease onset, previous incorrect diagnoses made and the recommended treatments. Results: There were 34 women, with a mean age at the diagnosis of 45.9 ± 12.2 years, and 28/48 (58%) of the patients were idiopathic. Negative sensory symptoms were the heralding symptoms in 25/48 (52%); these were asymmetric in 36/48 (75%) and followed a chronic course in 35/48 (73%). On average, it took 5.4 ± 5.3 years for SN to be diagnosed; patients had an average of 3.4 ± 1.5 incorrect diagnoses. A disease onset before the age of 40 was associated to shorter diagnosis delay (3.7 ± 3.4 vs. 7.8 ± 6.7 years, p = 0.01). Conclusions: These results suggest that diagnostic delay and misdiagnosis are frequent in non-paraneoplastic SN patients. As in other rare conditions, increased awareness in all the healthcare system levels is paramount to ensure accurate diagnosis and to improve care of these patients.

The elusive diagnosis of sensory neuronopathy

“…The odyssey described by Martinez et al 1 well describes the pitfalls and failings in identifying sensory neuronopathy as a clinical entity, which is understandable in the context of this complex and interrogation-resistant condition of heterogeneous cases and outcome. Many of us will recall memories of the frustration for both doctor and patient when faced with diagnostic challenges in this arena.…”