Difficulties in HAM/TSP diagnosis.

The World Health Organization recommends the use of Osame's criterion (1990) for the diagnosis of HTLV-I-associated myelopathy (HAM/TSP). In 2006, a group of neurologists developed a Brazilian criterion that can diagnose HAM/TSP from its onset. Objective: It was to test the agreement between both criteria. Methods: The study included evaluation of clinical and laboratory findings of 35 patients. The ELISA, Western blot and/or polymerase chain reaction was used to search for anti-HTLV-I antibodies. The analysis of agreement was based on the calculation of Kappa. Results: Concordance of 100% (Kappa=1) occurred in cases of "defined" HAM/TSP, but not in patients with "probable" diagnosis. Conclusion: The Brazilian criteria was as effective as Osame's criteria for the diagnosis of "defined" HAM/TSP. However, both require more specific biological markers in cerebrospinal fluid for the laboratory diagnosis of probable cases.