Polineuropatia por Parathion: estudo clinico, eletrofisiológico e histológico de um caso

Alonso, José L.; Atalla, Açucena; Cavaliere, Maria J.; Gagioti, Sonia M.; Lorenti, Maria A. A.

doi:10.1590/S0004-282X1983000300011

Resumos

Estudamos um paciente com quadro clínico rebelde, produzido por intoxicação pelo Parathion. Foi observado um fenômeno miotônico transitório, não descrito na literatura revisada. A constatação de cifras de AchE eritrocitária baixas e de colinesterase plasmática normais, indicou que era portador de déficit congênito de AchE, esclarecendo-se a evolução crônica do seu quadro. O fenômeno miotônico associado ao quadro clínico, eletrofisiológico, histológico e bioquímico fazem deste paciente um modelo clínico, de etiologia conhecida, da discutida síndrome de Isaacs.

A case of 38 year old man who worked with organochlorinated and Parathion during 5 years is reported. His follow-up was up to 2 years. The onset of the disease was characterized by cholinergic signs, headache, loss of weight, trembling, miokimias, fasciculations, ataxia, myotonic phenomena (in hands only) and motor sensitive peripheral polyneuropathy (affecting the lower limbs symmetrically). Low concentrations of blood cholinesterases confirmed the etiology. Myotonic phenomena disappeared spontaneuosly 6 months after the initial observation. One year later, the concentration of erytrocyte acetilcholinesterase was found to be low and plasma cholinesterase was normal, suggesting that the patient was carrier of a congenital deficiency of acetilcholinesterase. in literature relationship between myotonia and intoxication due to organophosphorus was not found. The whole clinical picture, cholinergic symptoms, transitory myotonic phenomena and spontaneous motor activity could be explained by an excess of acetilcholine. Eletromyography (EMG) in the first observation showed neuromuscular transmission blocking characterized by deficiency or absence of voluntary activity, unexcitability of fibular nerves, with fibrilations and positive peaks as described previously with Mipafox (another organophosphorus agent). During 2 years of observation numerous end-plates potentials of muscular fibres persisted in the EMG. A progressive increase in voluntary activity showed by unit motor potential of almost normal amplitude and very increased duration was observed. No potentials of reinnervation were noted. The results of EMG were explained as disturbances of neuromuscular transmission associated with moderate signs of denervation The Eaton-Lambert's test and the stimulation of a single unit motor potential confirmed disorder of neuromuscular synapses. The histochemistry of brachial biceps showed scattered atrophic and angulated type I and II fibres. Teased-fibres preparations showed nerve fibres with B, C, and G alterations as defined by Dyck et al. indicating axonal degeneration. These results were according to velocity of sensitive conduction. The conduction velocity of fibular nerves was strongly delayed during all the evolution indicating serious disorders of motor nerves myelin. We think that intoxication by organophosphorus should not be expressed as an identical alteration of both motor and sensitive nerves. The association of myotonic phenomena with such clinical, electrophysiological and histological picture is characteristic of the Isaac's syndrome model with known etiology.

Polineuropatia por Parathion: estudo clinico, eletrofisiológico e histológico de um caso

Polyneuropathy caused by Parathion: clinical, eletrophysiological and histological study of a case

José L. Alonso^I; Açucena Atalla^II; Maria J. Cavaliere^II; Sonia M. Gagioti^II; Maria A. A. Lorenti^III

^IMédico responsável pelo Setor de Eletromiografia. Clínica Neurológica e Serviço de Anatomia Patológica do Hospital do Servidor Público Estadual de São Paulo

^IIBióloga do Setor de Patologia Experimental. Clínica Neurológica e Serviço de Anatomia Patológica do Hospital do Servidor Público Estadual de São Paulo

^IIIMédica da Clínica Neurológica. Clínica Neurológica e Serviço de Anatomia Patológica do Hospital do Servidor Público Estadual de São Paulo

RESUMO

Estudamos um paciente com quadro clínico rebelde, produzido por intoxicação pelo Parathion. Foi observado um fenômeno miotônico transitório, não descrito na literatura revisada. A constatação de cifras de AchE eritrocitária baixas e de colinesterase plasmática normais, indicou que era portador de déficit congênito de AchE, esclarecendo-se a evolução crônica do seu quadro. O fenômeno miotônico associado ao quadro clínico, eletrofisiológico, histológico e bioquímico fazem deste paciente um modelo clínico, de etiologia conhecida, da discutida síndrome de Isaacs.

SUMMARY

A case of 38 year old man who worked with organochlorinated and Parathion during 5 years is reported. His follow-up was up to 2 years. The onset of the disease was characterized by cholinergic signs, headache, loss of weight, trembling, miokimias, fasciculations, ataxia, myotonic phenomena (in hands only) and motor sensitive peripheral polyneuropathy (affecting the lower limbs symmetrically). Low concentrations of blood cholinesterases confirmed the etiology. Myotonic phenomena disappeared spontaneuosly 6 months after the initial observation. One year later, the concentration of erytrocyte acetilcholinesterase was found to be low and plasma cholinesterase was normal, suggesting that the patient was carrier of a congenital deficiency of acetilcholinesterase. in literature relationship between myotonia and intoxication due to organophosphorus was not found. The whole clinical picture, cholinergic symptoms, transitory myotonic phenomena and spontaneous motor activity could be explained by an excess of acetilcholine. Eletromyography (EMG) in the first observation showed neuromuscular transmission blocking characterized by deficiency or absence of voluntary activity, unexcitability of fibular nerves, with fibrilations and positive peaks as described previously with Mipafox (another organophosphorus agent). During 2 years of observation numerous end-plates potentials of muscular fibres persisted in the EMG. A progressive increase in voluntary activity showed by unit motor potential of almost normal amplitude and very increased duration was observed. No potentials of reinnervation were noted. The results of EMG were explained as disturbances of neuromuscular transmission associated with moderate signs of denervation The Eaton-Lambert's test and the stimulation of a single unit motor potential confirmed disorder of neuromuscular synapses. The histochemistry of brachial biceps showed scattered atrophic and angulated type I and II fibres. Teased-fibres preparations showed nerve fibres with B, C, and G alterations as defined by Dyck et al. indicating axonal degeneration. These results were according to velocity of sensitive conduction. The conduction velocity of fibular nerves was strongly delayed during all the evolution indicating serious disorders of motor nerves myelin. We think that intoxication by organophosphorus should not be expressed as an identical alteration of both motor and sensitive nerves. The association of myotonic phenomena with such clinical, electrophysiological and histological picture is characteristic of the Isaac's syndrome model with known etiology.

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Trabalho realizado, com auxílio da Fundação de Amparo à Pesquisa do Estado de São Paulo na Clínica Neurológica e no Serviço de Anatomia Patológica do Hospital do Servidor Público Estadual de São Paulo.

Agradecimento - À Dra. Rosa Gaeta da Seção de Toxicologia e Higiene Comparada do Instituto Biológico de São Paulo, pela realização das dosagens de colinesterases no sangue; ao Dr. Flávio Rodrigues Puga, da mesma instituição, pelas dosagens de colinesterase eritrocitária e plasmática e da cromatografia de fase gasosa no plasma.

Trabalho realizado, com auxílio da Fundação de Amparo à Pesquisa do Estado de São Paulo na Clínica Neurológica e no Serviço de Anatomia Patológica do Hospital do Servidor Público Estadual de São Paulo.

Setor de Eletromiografia - Hospital do Servidor Público - Caixa Postal 8570 -01000 São Paulo, SP - Brasil.

1. ALONSO, J. L. - Reacciones de padrón miasténico en pacientes afectados de miotonia. Resumo. Excerpta med. internat. Congr. Ser. 296:69, 1973.
2. ALONSO, J. L.; BRUNONI, D. E. & PASCUZZI, L. - Distrofia miotônica. Estudo de uma família. Resumos. VII Congresso Brasileiro de Neurologia. Salvador, julho, 1976.
3. AMITAI, G.; ASHANI, Y.; SHAHAR, A.; GAFNI, A. & SILMAN, J. - Fluorescent organophosphates: Novel probes for studying aging-inducted conformational chances in inhibited acetylcholinesterase and for localization of cholinesterase in nervous tissue. Monog. neurol Sci.: vol. 7, pg. 70. Karger, Basel, 1980.
4. BEHMER, O. A.; TOLOSA, E. M. C. & FREITAS NETO, A. G. de - Manual de Técnicas para Histologia Normal e Patológica. Edart, São Paulo, 1976.
5. BIDSTRUP, P. L. & BONNEL, J. A. - Paralysis following poisoning by a new organic phosphorus inseticide (Mipafox). Brit. med. J. 1:1068, 1953.
6. BLACK, J. T.; GARCIA-MULLIN, R.; GOOD, E. & BROWNS, S. - Muscle rigidity in a newborn due to continous peripheral nerve hyperactivity. Arch. Neurol. (Chicago) 27:419, 1972.
7. CHAYEN, J.; BITENSKY, L. & BUTCHER, R. G. - Practical Histochemistry. John Willey & Sons, London, 1973.
8. DA SILVA, A. B.; JAAPP, H. H.; SALDANHA, A. P. D. & HENRIQUES, F. G. - Sindrome de Isaacs: registro de um caso e revisão da literatura. Arq. Neuro-Psiquiat. (São Paulo) 35:139, 1977.
9. DALE, W. E.; MILES, J. W. S. & GAINES, T. B. - Quantitative method for determination of DDT metabolites in blood serum. J. A. O. A. C. 53:1287, 1970.
10. DAVIES, J. E.; DAVIS, J. H.; FRAZIER, D. E.; MANN, J. B.; REICH, G. A. & TOCCI, P. M. - Disturbances of metabolism in organophosphate poisoning. Industr. Med. Surg. 36:58, 1967.
11. DAVIGNON, L. F.; ST-PIERRE, J.; CHAREST, G. & TOURANGEAU, F. J. - A study of the chronic effects of inseticides in man. J. Assoc. méd. canad. 92:597, 1965.
12. DILLE, J. R. & SMITH, P. W. - Central nervous system effects of chronic exposure to organophosphate inseticides. Aerospace Med. 35:475, 1965.
13. DIXON, E. M. - Dilatation of the pupils in parathion poisoning. JAMA 163:444, 1957.
14. DUBOWITZ, V. & BROOKE, M. H. - Histological and Histochemical Stains and Reactions in Muscle Biopsy: a Modern Approach. Saunders, London, 1973.
15. DYCK, P. J. - Pathologic alterations of the peripheral nerves systems of man. In DYCK, P. J.; THOMAS, P. K. & LAMBERT, E. H., eds. - Peripheral Neuropathy. Saunders, Philadelphia, 1975.
16. DYCK, P. J.; JOHNSON, W. J.; LAMBERT, E. H. & O'BRIEN, P. C. - Segmental demyelination secondary to axonal degeneration in uremic neuropathy. Mayo Clin. Proc. 46:400, 1971.
17. DYCK, P. J. & LOFGEN, E. P. - Nerve biopsy: choice of nerve, method, symptoms and usefulness. Med. Clin. N. Amer. 52:885, 1968.
18. EDSON, E. F. - Blood tests to users of O.P. insecticides. World. Crops. 10:49, 1958.
19. ELLIOTT, H. W. & BOKUMS, J. A. - Effects of pralidoxime on electrical activity of the cat brain. Proc. Soc. exp. Biol. Med. 129:443, 1968.
20. FORSTER, F. M. & ALPERS, B. J. - Site of origin of fasciculations in voluntary muscle. Arch. Neurol. Psychiat. (Chicago) 51:264, 1944.
21. FORSTER, F. M.; BORKOWSKI, W. J.
22 GAETA, R.; PUGA, F. R. & MELLO, D. - Determinação da atividade da colinesterase em trabalhadores expostos à ação de monocrotofós, inseticida fosforado orgânico. O Biológico (São Paulo) 41:73, 1975.
23. GAMSTORP, I. & WOHLFART, G. - A syndrome characterized by myokymia, myotonia, muscular wasting and increased perspiration. Acta Psychiat. scand. 34:181, 1959.
24. GOLDIN, A. R.; RUBENSTEIN, A. H.; BRADLOW, B. A.; PATH, D.; PATH, M. C. & ELLIOTT, G. A. - Malathion poisoning with special reference to the effect of cholinesterase inhibition on erythrocyte survial. New Engl. J. Med. 271:1289, 1964.
25. GOLDMAN, H. & TEITEL, M. - Malathion poisoning in a 34 month-old child following accidental ingestion. J. Pediatr. 52:76, 1958.
26. GROB, D.; HARVEY, A. M.; LANGWORTHY, O. R. & LILIENTHAL, J. L. - The administration of di-isopropryl fluorophosphate (DEP) to man. Bull. Johns Hopkins Hosp. 81:257, 1947.
27. HOTTINGER, A. & BLOCH, H. - Ueber die spezifitat der Cholinesterase-Nemmung durch tri-o-kresylphosphat. Helvet. chim. Acta, 26:142, 1943.
28. IGISU, H.; ANTOKU, Y.; MAWATARI, S. & KUROIWA, Y. - Erythrocyte membrane in myotonic dystrophy. A study acetylcholinesterase. J. neurol. Sci. 51:199, 1981.
29. ISAACS, H. - A syndrome of continous muscle-fibre activity. J. Neurol. Neuro-surg. Psychiat. 24:319, 1961.
30. ISAACS, H. - Continous muscle fibre activity in an indian male with additional evidence of terminal motor fibre abnormality. J. Neurol. Neurosurg. Psychiat. 30:126, 1967.
31. JAGER, A. E. J.; VAN WERDEN, T. W.; HONTROFF, H. J. & de MONCHY, J. G. R. - Polincuropaty after massive exposure to Parathion. Neurol. (Mi-neapolis) 31:603, 1981.
32. JENKINS, R. B. & TOOLE, J. F. - Polyneuropathy following exposure to insecticides. Arch. int. Med. 113:691, 1964.
33. JOHNSON, M. K. - Organophosphorus esters causing delayed neurotoxic effects. Arch. Toxicol. (Berlin) 34:259, 1975.
34. JOHNSON, M. K. - Irreversible Phosphorylation of Brain Neurotoxic Esterase. Monogr. neurol. Sci.: vol. 7, pg. 99. Karger, Basel, 1980.
35. LEVY, J. A.; WITTIG, E. O. & FERRAZ, E. C. F. - Escleroderma associada a atividade elétrica muscular contínua. Arq. Neuro-Psiquiat. (São Paulo) 23:283, 1965.
36. LTJDIN, H. P. - Fundamentos Fisiopatológicos de la Electromiografia. Toray, Barcelona, 1974.
37. McCOMAS, A. J. - Neuromuscular Function and Diseases. Buterworths, London, 1977.
38. McCOMAS, A. J.; CAMPBELL, M. J. & SICA, R. E. P. - Electrophysiological study of dystrophia myotonica. J. Neurol. Neurosurg. Psychiat 34:132, 1971.
39. MEJIAS, M. R. - Intoxicacion aguda por inseticidas organofosforados: estudio clínico em adultos y experimental en perros. Tese. Universidade Peruana Cayetano Heradia, Lima, 1972.
40. MENDONÇA, L. Z. - Atividade elétrica contínua de fibra muscular. In LEVY, J. A. ed. - Miopatias. Atheneu, São Paulo, 1978.
41. MERTENS, H. G. Sc ZSCHOCKE, S. - Neuromyotonia. Klin. Wschr. 43:917, 1965.
42. NAMBA, T.; NOLTE, C. T.; JACREL, J. & GROB, D. - Poisoning due to organophosphate inseticides. Am. J. Med. 50:475, 1971.
43. NOVAK, E. M. & WERNECK, L. C. - Comprometimento neurológico por inseticidas: estudo das manifestações clínicas em 13 casos. Arq. Neuro-Psiquiat. (São Paulo) 35:129, 1977.
44. PETRY, H. - Polineuritis durch E.605. Zentralbl. Arbeitsmed. Arbeitsschutz. 1:86, 1951.
45. PETTY, C. S. - Organic phosphate inseticide poisoning: residual effects in two cases. Am. J. Med. 24:467, 1958.
46. ROCHA, E. E. M.; OLIVEIRA, F.; MORINIGO, F. & HONIGMAN, I. - Intoxicações por inseticidas. J. bras. Med. 23:152, 1972.
47. SARAIVA, S. & ASSIS, J. L. - Associação familiar de miastenia grave e sindrome miotônica. Arq. Neuro-Psiquiat. (São Paulo) 27:328, 1969.
48. SMITH, M. J. & LILLIE R. D. - Histopathology of triorthocresyl-phosphate poisoning: the etiology of socalled ginger-paralysis (third report). Arch. Neurol. Psychiat. (Chicago) 26:976, 1931.
49. WALLIS, W. E.; POZNAK, A. V. & PLUM, F. - Generalized mi scular stiffness, fasciculations, and myokymia of peripheral nerve origin. Arch. Neurol. (Chicago) 22:430, 1970.
50. WELCH, L. H.; APPENZELLER, O. & BICKNELL, J. M. - Peripheral neuropathy with myokymia, sustained muscular contraction and continous motor unit acticity. Neurol. (Minneapolis) 22:969, 1972.
51. WELLER, R. O. & CERVÓS-NAVARRO, J. - Pathology of Peripheral Nerves. Butterworths, London, 1977.
52. WERNECK, L. C. & NOVAK, E. M. - Intoxicações por inseticidas: micro-dissecção de nervos e histoquímica de músculos em 10 casos. Arq. Neuro-Psiquiat. (São Paulo) 37:15, 1979.
53. WILCHER, D. O. & WARMOLTS, J. R. - Anterior horn cell diseases. In Johnson, E. W. ed. - Practical Electromyography. Williams & Wilkins, Baltimore, 1980.
54. WIEDERHOLT, W. C. - End-plate noise in electromyography. - Neurol. (Minneapolis) 20:214, 1970.
55. WILHELM, K. - Determination of human plasma colinesterase activity by adapted Ellman's method. Arch. hig. rada. 199:207, 1968.

Datas de Publicação

Publicação nesta coleção
14 Ago 2012
Data do Fascículo
Set 1983

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] 1. ALONSO, J. L. - Reacciones de padrón miasténico en pacientes afectados de miotonia. Resumo. Excerpta med. internat. Congr. Ser. 296:69, 1973.

[2] 2. ALONSO, J. L.; BRUNONI, D. E. & PASCUZZI, L. - Distrofia miotônica. Estudo de uma família. Resumos. VII Congresso Brasileiro de Neurologia. Salvador, julho, 1976.

[3] 3. AMITAI, G.; ASHANI, Y.; SHAHAR, A.; GAFNI, A. & SILMAN, J. - Fluorescent organophosphates: Novel probes for studying aging-inducted conformational chances in inhibited acetylcholinesterase and for localization of cholinesterase in nervous tissue. Monog. neurol Sci.: vol. 7, pg. 70. Karger, Basel, 1980.

[4] 4. BEHMER, O. A.; TOLOSA, E. M. C. & FREITAS NETO, A. G. de - Manual de Técnicas para Histologia Normal e Patológica. Edart, São Paulo, 1976.

[5] 5. BIDSTRUP, P. L. & BONNEL, J. A. - Paralysis following poisoning by a new organic phosphorus inseticide (Mipafox). Brit. med. J. 1:1068, 1953.

[6] 6. BLACK, J. T.; GARCIA-MULLIN, R.; GOOD, E. & BROWNS, S. - Muscle rigidity in a newborn due to continous peripheral nerve hyperactivity. Arch. Neurol. (Chicago) 27:419, 1972.

[7] 7. CHAYEN, J.; BITENSKY, L. & BUTCHER, R. G. - Practical Histochemistry. John Willey & Sons, London, 1973.

[8] 8. DA SILVA, A. B.; JAAPP, H. H.; SALDANHA, A. P. D. & HENRIQUES, F. G. - Sindrome de Isaacs: registro de um caso e revisão da literatura. Arq. Neuro-Psiquiat. (São Paulo) 35:139, 1977.

[9] 9. DALE, W. E.; MILES, J. W. S. & GAINES, T. B. - Quantitative method for determination of DDT metabolites in blood serum. J. A. O. A. C. 53:1287, 1970.

[10] 10. DAVIES, J. E.; DAVIS, J. H.; FRAZIER, D. E.; MANN, J. B.; REICH, G. A. & TOCCI, P. M. - Disturbances of metabolism in organophosphate poisoning. Industr. Med. Surg. 36:58, 1967.

[11] 11. DAVIGNON, L. F.; ST-PIERRE, J.; CHAREST, G. & TOURANGEAU, F. J. - A study of the chronic effects of inseticides in man. J. Assoc. méd. canad. 92:597, 1965.

[12] 12. DILLE, J. R. & SMITH, P. W. - Central nervous system effects of chronic exposure to organophosphate inseticides. Aerospace Med. 35:475, 1965.

[13] 13. DIXON, E. M. - Dilatation of the pupils in parathion poisoning. JAMA 163:444, 1957.

[14] 14. DUBOWITZ, V. & BROOKE, M. H. - Histological and Histochemical Stains and Reactions in Muscle Biopsy: a Modern Approach. Saunders, London, 1973.

[15] 15. DYCK, P. J. - Pathologic alterations of the peripheral nerves systems of man. In DYCK, P. J.; THOMAS, P. K. & LAMBERT, E. H., eds. - Peripheral Neuropathy. Saunders, Philadelphia, 1975.

[16] 16. DYCK, P. J.; JOHNSON, W. J.; LAMBERT, E. H. & O'BRIEN, P. C. - Segmental demyelination secondary to axonal degeneration in uremic neuropathy. Mayo Clin. Proc. 46:400, 1971.

[17] 17. DYCK, P. J. & LOFGEN, E. P. - Nerve biopsy: choice of nerve, method, symptoms and usefulness. Med. Clin. N. Amer. 52:885, 1968.

[18] 18. EDSON, E. F. - Blood tests to users of O.P. insecticides. World. Crops. 10:49, 1958.

[19] 19. ELLIOTT, H. W. & BOKUMS, J. A. - Effects of pralidoxime on electrical activity of the cat brain. Proc. Soc. exp. Biol. Med. 129:443, 1968.

[20] 20. FORSTER, F. M. & ALPERS, B. J. - Site of origin of fasciculations in voluntary muscle. Arch. Neurol. Psychiat. (Chicago) 51:264, 1944.

[21] 21. FORSTER, F. M.; BORKOWSKI, W. J.

[22] 22 GAETA, R.; PUGA, F. R. & MELLO, D. - Determinação da atividade da colinesterase em trabalhadores expostos à ação de monocrotofós, inseticida fosforado orgânico. O Biológico (São Paulo) 41:73, 1975.

[23] 23. GAMSTORP, I. & WOHLFART, G. - A syndrome characterized by myokymia, myotonia, muscular wasting and increased perspiration. Acta Psychiat. scand. 34:181, 1959.

[24] 24. GOLDIN, A. R.; RUBENSTEIN, A. H.; BRADLOW, B. A.; PATH, D.; PATH, M. C. & ELLIOTT, G. A. - Malathion poisoning with special reference to the effect of cholinesterase inhibition on erythrocyte survial. New Engl. J. Med. 271:1289, 1964.

[25] 25. GOLDMAN, H. & TEITEL, M. - Malathion poisoning in a 34 month-old child following accidental ingestion. J. Pediatr. 52:76, 1958.

[26] 26. GROB, D.; HARVEY, A. M.; LANGWORTHY, O. R. & LILIENTHAL, J. L. - The administration of di-isopropryl fluorophosphate (DEP) to man. Bull. Johns Hopkins Hosp. 81:257, 1947.

[27] 27. HOTTINGER, A. & BLOCH, H. - Ueber die spezifitat der Cholinesterase-Nemmung durch tri-o-kresylphosphat. Helvet. chim. Acta, 26:142, 1943.

[28] 28. IGISU, H.; ANTOKU, Y.; MAWATARI, S. & KUROIWA, Y. - Erythrocyte membrane in myotonic dystrophy. A study acetylcholinesterase. J. neurol. Sci. 51:199, 1981.

[29] 29. ISAACS, H. - A syndrome of continous muscle-fibre activity. J. Neurol. Neuro-surg. Psychiat. 24:319, 1961.

[30] 30. ISAACS, H. - Continous muscle fibre activity in an indian male with additional evidence of terminal motor fibre abnormality. J. Neurol. Neurosurg. Psychiat. 30:126, 1967.

[31] 31. JAGER, A. E. J.; VAN WERDEN, T. W.; HONTROFF, H. J. & de MONCHY, J. G. R. - Polincuropaty after massive exposure to Parathion. Neurol. (Mi-neapolis) 31:603, 1981.

[32] 32. JENKINS, R. B. & TOOLE, J. F. - Polyneuropathy following exposure to insecticides. Arch. int. Med. 113:691, 1964.

[33] 33. JOHNSON, M. K. - Organophosphorus esters causing delayed neurotoxic effects. Arch. Toxicol. (Berlin) 34:259, 1975.

[34] 34. JOHNSON, M. K. - Irreversible Phosphorylation of Brain Neurotoxic Esterase. Monogr. neurol. Sci.: vol. 7, pg. 99. Karger, Basel, 1980.

[35] 35. LEVY, J. A.; WITTIG, E. O. & FERRAZ, E. C. F. - Escleroderma associada a atividade elétrica muscular contínua. Arq. Neuro-Psiquiat. (São Paulo) 23:283, 1965.

[36] 36. LTJDIN, H. P. - Fundamentos Fisiopatológicos de la Electromiografia. Toray, Barcelona, 1974.

[37] 37. McCOMAS, A. J. - Neuromuscular Function and Diseases. Buterworths, London, 1977.

[38] 38. McCOMAS, A. J.; CAMPBELL, M. J. & SICA, R. E. P. - Electrophysiological study of dystrophia myotonica. J. Neurol. Neurosurg. Psychiat 34:132, 1971.

[39] 39. MEJIAS, M. R. - Intoxicacion aguda por inseticidas organofosforados: estudio clínico em adultos y experimental en perros. Tese. Universidade Peruana Cayetano Heradia, Lima, 1972.

[40] 40. MENDONÇA, L. Z. - Atividade elétrica contínua de fibra muscular. In LEVY, J. A. ed. - Miopatias. Atheneu, São Paulo, 1978.

[41] 41. MERTENS, H. G. Sc ZSCHOCKE, S. - Neuromyotonia. Klin. Wschr. 43:917, 1965.

[42] 42. NAMBA, T.; NOLTE, C. T.; JACREL, J. & GROB, D. - Poisoning due to organophosphate inseticides. Am. J. Med. 50:475, 1971.

[43] 43. NOVAK, E. M. & WERNECK, L. C. - Comprometimento neurológico por inseticidas: estudo das manifestações clínicas em 13 casos. Arq. Neuro-Psiquiat. (São Paulo) 35:129, 1977.

[44] 44. PETRY, H. - Polineuritis durch E.605. Zentralbl. Arbeitsmed. Arbeitsschutz. 1:86, 1951.

[45] 45. PETTY, C. S. - Organic phosphate inseticide poisoning: residual effects in two cases. Am. J. Med. 24:467, 1958.

[46] 46. ROCHA, E. E. M.; OLIVEIRA, F.; MORINIGO, F. & HONIGMAN, I. - Intoxicações por inseticidas. J. bras. Med. 23:152, 1972.

[47] 47. SARAIVA, S. & ASSIS, J. L. - Associação familiar de miastenia grave e sindrome miotônica. Arq. Neuro-Psiquiat. (São Paulo) 27:328, 1969.

[48] 48. SMITH, M. J. & LILLIE R. D. - Histopathology of triorthocresyl-phosphate poisoning: the etiology of socalled ginger-paralysis (third report). Arch. Neurol. Psychiat. (Chicago) 26:976, 1931.

[49] 49. WALLIS, W. E.; POZNAK, A. V. & PLUM, F. - Generalized mi scular stiffness, fasciculations, and myokymia of peripheral nerve origin. Arch. Neurol. (Chicago) 22:430, 1970.

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