Self-injurious behavior in acquired sensory neuropathy

Delayed Effects of Transcutaneous Organophosphate Poisoning in Four Children

Contamination or transcutaneous absorption of organophosphates (OP) is rare and there exist only few reports of such manner of poisoning. We report four children from the same family in whom temporal proximity of the disease onset, a detailed interrogation of parents and exclusion of other clinical differentials, led to the diagnosis of transcutaneous intoxication with organophosphates (diazinon). The contamination occurred during the game with a freshly used poison can. Uncommon clinical picture was marked by delayed signs predominantly reflecting certain nicotinic effects (muscle weakness, cramps) along with subtle neuropathic features occurring throughout a few weeks after initial event. Our illustrative cases can further contribute to the better awareness and understanding of variable spectrum of transcutaneous route of OP poisoning.

Self-injurious behavior in neurodevelopmental disorders: relevance of nociceptive and immune mechanisms

Self-injurious behavior (SIB) among individuals with intellectual and related neurodevelopmental disorders (IDD) is a clinical challenge and scientific puzzle. The physiological mechanisms regulating the sensory components of SIB remain a mystery with no clear understanding of the underlying pathophysiology. The central dogma regarding sensory processing in general and pain in particular among individuals with IDD and chronic SIB is that sensory processing is reduced and pain is absent or blunted. In this paper, recent findings challenging some of the conventional wisdom regarding pain and sensory function among individuals with IDD and SIB are reviewed. It seems that at least a subgroup of individuals with IDD and chronic SIB may be in a physiological state similar to neuropathic pain in which hyperalgesia is mediated by plasticity mechanisms regulating inflammatory, immune, and nociceptive systems. In response to repeated tissue damage associated with chronic self-injury, innate immune cells may be producing pro-inflammatory and pro-nociceptive cytokines that act on the brain to cause sickness-like behavior and sensitize primary sensory nerve afferents contributing to pain hypersensitivity (i.e., hyperalgesia).

Treatment of life-threatening self-injurious behavior secondary to hereditary sensory and autonomic neuropathy type II: a controlled case study

Although self-injurious behavior is present in all subtypes of hereditary sensory and autonomic neuropathy, the literature has not sufficiently addressed the issue of treatment of self-injury in this population. Therefore, the purpose of the current case study was to describe a method for assessing and treating self-injurious behavior associated with hereditary sensory and autonomic neuropathies. This study was conducted with an 11-year-old boy diagnosed with hereditary sensory and autonomic neuropathy type II admitted to an inpatient behavioral unit over a 4-month period. A simplified version of a habit reversal treatment was used, consisting of awareness training, self-monitoring, competing responses, and social support. Treatment resulted in a 98% reduction in the rate of self-injurious behavior relative to pretreatment baseline rates. This case study illustrates that behavioral interventions may be a viable option for treating self-injury secondary to hereditary sensory and autonomic neuropathies.

A prospective clinical analysis of pain behavior and self-injurious behavior

It is a widely assumed but rarely tested proposition that the experience and expression of pain is altered among individuals with self-injurious behavior and disabilities. As a preliminary test of this proposition, the purpose of this case study was to apply a validated pain measure to examine ratings of pain behavior in relation to ratings of self-injurious behavior (SIB). A prospective correlational design was used with maternal ratings completed three times/day for 9 days using two item independent rating scales specific to pain and SIB. The participant was a 6-year-old boy with severe SIB secondary to midbrain tumor (pilocytic astrocytoma) resection and post-operative sequelae. Measures were taken in the child's home. Pain behavior was measured using the Non-Communicating Children's Pain Checklist Revised (NCCPC-R). Self-injury was measured using the Self-Injury Trauma Scale (SITS). Time intervals associated with elevated ratings of SIB were associated with elevated pain ratings. There was a significant difference (P<0.05) for pain ratings between time intervals with and without self-injury. It is suggested that additional empirical work is needed to clarify the relation between pain and self-injury to improve assessment and treatment outcomes.

Carbamazepine trial for Lesch-Nyhan self-mutilation

Anticonvulsants may reduce the self-mutilation of acquired sensory neuropathy, and one report described sensory neuropathy in an older patient with Lesch-Nyhan syndrome. We performed nerve and muscle biopsies on four patients with Lesch-Nyhan syndrome and initiated an uncontrolled pilot trial to see if carbamazepine would reduce the self-mutilation in these patients. All of the boys had clinical features typical of Lesch-Nyhan syndrome, and the diagnosis was confirmed in each by enzyme analysis. No specific abnormalities were identified in either nerve or muscle. Nevertheless, self-mutilation and the need for constant restraint diminished in all four patients, though in one the effect was only transient. Two patients had increased self-mutilation when carbamazepine was stopped, then improved a second time when treatment was restarted. Sensory neuropathy was not confirmed, so any effect of carbamazepine is likely to be on the central nervous system.