Neuronal Depletion in Chagas' Disease: Everything Must be Revised

pp 239-246

Abstract

Background

After twenty years the discussion about the presence and importance of the difuse loss of neurovegetative neurons in the chronic chagasic cardiomyopathy is discussed. This lesion was wrongly considered as a cardinal sign of the disease. Due to a conceptual mistake, the neuronal diminution of the normal cardiac neurovegetative ganglia that contain a less number of neurons, as compared to those containing a maximal number of neurons, was wrongly diagnosed as a classic neuronal depletion. A more attentive approach to the basic features of the purported neuronal depletion now reveal that the histological diagnostic criteria adopted for assessing a neuronal depletion are patently insufficient and unreliable. The statistical comparison between normal cardiac ganglia and supposedly neuron-depleted ones has been based on arbitrary terms, in so far a sit does not take into consideration the remarkable variations in number of right atrial ganglia, and their richness in nerve cells, among normal subjects. Data in the literature concerning autonomic nervous system pathology clearly demonstrate that any "neuronal loss" in peripheral autonomic ganglia is counter-signed by an accompaning nodular proliferation of the satellite capsular cells; these provide a sort of "neuronal scar" by the final replacement of the dead ganglion cell body with the so-called Terplan nodule. Instead, illustrations of pretended classic features of neuron-depleted ganglia in chagasic hearts fail to exhibit any evidence of Terplan nodules while stating the loss of neurons, leaving no trace of their former presence, whats over.

Conclusions

The dysautonomic symptoms manifested by a minority of chagasic cardiac patients could rather be mainly a scribed to the histopathological evidence of chronic neuritis `(peri and endoneuritis) often observed in chagasic hearts. The treatment with gangliosides would be effective, perhaps only in cases of neuritis, because nothing can regenerate a "lost neuron".