Infectious diseases causing autonomic dysfunction.

OBJECTIVES: To review infectious diseases that may cause autonomic dysfunction. METHODS: Review of published papers indexed in medline/embase. RESULTS: Autonomic dysfunction has been reported in retrovirus (human immunodeficiency virus (HIV), human T-lymphotropic virus), herpes viruses, flavivirus, enterovirus 71 and lyssavirus infections. Autonomic dysfunction is relatively common in HIV-infected patients and heart rate variability is reduced even in early stages of infection. Orthostatic hypotension, urinary dysfunction and hypohidrosis have been described in tropical spastic paraparesis patients. Varicella zoster reactivation from autonomic ganglia may be involved in visceral disease and chronic intestinal pseudo-obstruction. Autonomic and peripheral nervous system dysfunction may happen in acute tick-borne encephalitis virus infections. Hydrophobia, hypersalivation, dyspnea, photophobia, and piloerection are frequently observed in human rabies. Autonomic dysfunction and vagal denervation is common in Chagas disease. Neuronal depopulation occurs mainly in chagasic heart disease and myenteric plexus, and megacolon, megaesophagus and cardiomyopathy are common complications in the chronic stage of Chagas disease. Parasympathetic autonomic dysfunction precedes left ventricle systolic dysfunction in Chagas disease. A high prevalence of subclinical autonomic neuropathy in leprosy patients has been reported, and autonomic nerve dysfunction may be an early manifestation of the disease. Autonomic dysfunction features in leprosy include anhidrosis, impaired sweating function, localised alopecia ,and reduced heart rate variability. Urinary retention and intestinal pseudo-obstruction have been described in Lyme disease. Diphtheritic polyneuropathy, tetanus and botulism are examples of bacterial infections releasing toxins that affect the autonomic nervous system. CONCLUSIONS: Autonomic dysfunction may be responsible for additional morbidity in some infectious diseases.

Skin and muscle vasomotor reflexes in detecting autonomic dysfunction in leprosy.

There are few tests to assess the function of small unmyelinated nerve fibers. One established test is the skin vasomotor reflex (SVMR), which uses laser doppler flow velocimetry. The SVMR has the disadvantages of being susceptible to interference (from change of temperature and alerting stimuli) and of requiring expensive equipment. An ultrasound doppler method, which is less expensive, can be used to detect muscle vasomotor reflex (MVMR) activity. We sought to compare the efficacy of these two methods in detecting dysfunction of small unmyelinated nerve fibers in patients with leprosy. SVMR was shown to be less sensitive (P < 0.01) and specific (P < 0.001) than MVMR. The favorable results of MVMR may be attributed to its lesser susceptibility to interfering sympathetic vasoconstriction from alerting stimuli. MVMR also reflects larger areas of blood vessel innervation than the laser doppler method. In leprosy, nerve damage is typically patchy and may be missed by the smaller sampling of the laser method.

Peripheral autonomic nerve dysfunction in asymptomatic leprosy contacts.

In endemic areas, subclinical autonomic nerve dysfunction may be a manifestation of infection with M. leprae and possibly allow detection before progression to clinical disease. Vasomotor reflex (VMR) testing was performed in 36 asymptomatic leprosy contacts (24 household contacts, 12 hospital contacts) and 47 age- and sex-matched controls in Pokhara, Nepal. Mean age was 30 years, two thirds were male. A Moor instruments DRT4 laser doppler monitor was used for velocimetry of microvascular blood flow. The flow reduction following an inspiratory gasp was recorded from finger and toe tips. Mean percent reduction was 57.8 (standard deviation 14.6) among household contacts, 61.9 (17.5) among hospital contacts and 66.8 (7.8) among controls (p=0.001 by analysis of variance). The prevalence of abnormal test results was 54% among household contacts, 42% among hospital contacts and 15% among controls (p=0.0005 by chi-square test for trend). Subclinical autonomic neuropathy is common among healthy contacts of leprosy patients. Prospective studies are now needed to clarify to what extent abnormal VMR tests predict the risk of progression to clinical disease.

Trastornos neurológicos de la lepra: aspectos troficos / Neural lesions of the leprosy: trophic aspects

El autor presenta la experiencia desarrollada durante los últimos seis años en el Consultorio de Ortopedia del Servicios de Dermato-leprología del Hospital Muñiz de Buenos Aires, lapso durante el cual se asistieron en dicho Consultorio alrededor de 500 enfermos. Se identifican los varios mecanismos lesionales de los nervios periféricos en lepra, así como su frecuencia relativa y los sitios topográficos de compromiso habitual. Se categorizan las funciones del sistema nervioso periférico en los miembros distinguiendo cuatro grupos: área motora, sensibilidad superficial, sensibilidad profunda y actividad neurovegetativa. El déficit de cada una de estas capacidades determina las diversas "lesiones tróficas", tales como parálisis y deformidades, mal perforante, artropatías neuropáticas, alteraciones del tegumento, etc. La infección secundaria de cualquiera de estas lesiones, al evolucionar en un terreno indoloro, suele carecer de tratamiento temprano y determina cuadros sépticos graves que compromenten el miembro afectado y provocan severas mutilaciones. Se enfatiza, finalmente, la necesidad de realizar campañas de Educación Sanitaria que alerten a los pacientes sobre la necesidad de consulta inmediata, aún ante lesiones mínimas e indoloras, cuyo tratamiento es simple y su curación no deja secuelas

Trastornos neurológicos de la lepra: aspectos troficos / Neural lesions of the leprosy: trophic aspects

El autor presenta la experiencia desarrollada durante los últimos seis años en el Consultorio de Ortopedia del Servicios de Dermato-leprología del Hospital Muñiz de Buenos Aires, lapso durante el cual se asistieron en dicho Consultorio alrededor de 500 enfermos. Se identifican los varios mecanismos lesionales de los nervios periféricos en lepra, así como su frecuencia relativa y los sitios topográficos de compromiso habitual. Se categorizan las funciones del sistema nervioso periférico en los miembros distinguiendo cuatro grupos: área motora, sensibilidad superficial, sensibilidad profunda y actividad neurovegetativa. El déficit de cada una de estas capacidades determina las diversas "lesiones tróficas", tales como parálisis y deformidades, mal perforante, artropatías neuropáticas, alteraciones del tegumento, etc. La infección secundaria de cualquiera de estas lesiones, al evolucionar en un terreno indoloro, suele carecer de tratamiento temprano y determina cuadros sépticos graves que compromenten el miembro afectado y provocan severas mutilaciones. Se enfatiza, finalmente, la necesidad de realizar campañas de Educación Sanitaria que alerten a los pacientes sobre la necesidad de consulta inmediata, aún ante lesiones mínimas e indoloras, cuyo tratamiento es simple y su curación no deja secuelas

Cardiovascular dysautonomia in patients with lepromatous leprosy.

Autonomic functions were studied by six standard tests in 65 patients with lepromatous leprosy and 25 healthy controls. Dysautonomia was observed in 22 patients, all having the disease for more than five years. Associated peripheral neuropathy, judged clinically, was present in all, except one patient. Of the 22 dysautonomic patients, 9 each had mild or moderate dysantonomia and 4 had severe dysautonomia as per the scoring schedule devised by us. Syncope, gustatory sweating and impotence were the symptoms suggestive of dysautonomia. But not all affected patients reported these symptoms. Involvement of the sympathetic system was more frequent than that of the parasympathetic system. Statistically significant abnormality was seen with Atropine ratio, standing 30:15 beat ratio, postural hypotension and sustained hand grip test. Sustained hand grip test was the one which consistently gave abnormal results in all the 22 dysautonomic patients.

Ocular autonomic dysfunction and intraocular pressure in leprosy.

We examined 241 leprosy patients and 135 age-matched healthy controls in central South Korea, measuring intraocular pressure in the supine and the upright positions and measuring the size of the pupils in darkness as an indication of ocular autonomic dysfunction. The mean intraocular pressure was significantly lower in the patients and the mean size of pupils was significantly smaller in the patients than in the controls. However, there was no correlation between pupil size and intraocular pressure in our patients. Our findings show that leprosy patients have ocular autonomic dysfunction, but do not support previous speculation that this dysfunction is the primary cause for low intraocular pressure in leprosy.

Autonomic neuropathy in leprosy.

21 patients of borderline lepromatous and lepromatous leprosy of both sexes were taken for study after exclusion of autonomic disorders. Autonomic functions pertaining to cardiovascular and genital system were carried out. Five healthy volunteers served as controls. Autonomic function tests indicate definite involvement of cardiovascular and genital system. The incidence of autonomic neuropathy in 21 patients studied was ranging from 14.3 to 57% for various tests. There is involvement of parasympathetic system (vagus nerve) which occurred early and more common than sympathetic. The sympathetic damage is always associated with parasympathetic damage. The severity of automatic neuropathy is found to be high in leprosy of longer duration. Autonomic neuropathy widely occurs in leprosy as in diabetes mellitus.