CLINICAL-DIAGNOSIS IN KARWINSKIA-HUMBOLDTIANA POLYNEUROPATHY

Intoxication by Karwinskia humboldtiana presents a neurological pictur e similar to that for Guillain-Barre syndrome or other polyradiculoneu ropathies. Clinical diagnosis in poisoned humans may be difficult if n o evidence of previous fruit ingestion is available. We present our ex perience in the clinical diagnosis of Karwinskia humboldtiana polyneur opathy, as confirmed by toxin detection in blood. We designed an open trial at the Pediatric Neurology service and included all cases with a cute ascending paralysis that were admitted to our hospital in the las t two years. In all cases, we performed hematological, immunological a nd biochemical profiles, CSF analysis including immunological studies, oligoclonal bands and myelin basic protein determinations. Electrodia gnostic studies were performed, including motor conduction velocities, distal latencies, F-wave latency and compound muscle action potential (CAMP) amplitude. The presence of Karwinskia humboldtiana toxins in b lood were determined by thin layer chromatography. In six cases, T-514 Karwinskia humboldtiana toxin was detected. These cases had a symmetr ic motor polyneuropathy with the absence of tendon reflexes and no sen sory signs or cranial nerve involvement. Only one patient required ass isted ventilation due to bulbar paralysis. In two of these cases, a su ral nerve biopsy revealed a segmental demyelination with swelling and phagocytic chambers in Schwann cells and without lymphocytic infiltrat ion. All six cases survived, with complete recovery in five. We conclu de that this intoxication is common in Mexico. The availability of tox in detection in blood samples allows the clinician to establish an acc urate diagnosis and should be included in the study of children with p olyradiculoneuropathy, especially in countries where this poisonous pl ant grows. (C) 1998 Elsevier Science B.V.