Dear Editor,
With interest, we read the article by Richardson and colleagues on organophosphate poisoning (OP), a topic of multi- and interdisciplinary relevance.1 We have the following comments and concerns. Organophosphates have been one of the most used pesticides since the mid-20th century. The first organophosphate to be synthesized, in 1854, was tetraethylpyrophosphate, and there are currently thousands of known formulations of organophosphate pesticides widely used as insecticides. The use of these products creates a serious public health problem. Among the clinical manifestations of OP, we would like to draw attention to neuropathy.
Toxic neuropathy (TN) is caused by voluntary or involuntary contact with numerous organic and nonorganic chemicals, such as organic solvents, heavy metals, drugs (chemotherapeutics, antiarrhythmics), biotoxins, alcohol, and organophosphate agents, among others. TN is less frequent than metabolic, inflammatory, and hereditary conditions, reported in 2% to 4% of cases as a cause of neuropathy.2,3 In contrast, TN has preventable causes, and when identified early, it can be reversed or disease progression can be impeded, avoiding unnecessary expenses and invasive investigations. TN caused by OP allows us to reflect on three important issues in medical practice: autotoxicity, late neuropathy, and subclinical findings.
Autotoxicity, whether through suicidal intent or through frequent or occasional contact with a toxic agent, is a phenomenon that deserves recognition in preventive and occupational medicine, valuing psychosocial aspects in clinical history.
Exposure to organophosphates, which may be transdermal, respiratory, or digestive, leads to manifestations of neurologic, behavioral, and psychiatric syndromes of acute, subacute, or chronic evolution; among them, late polyneuropathy appears as the most common chronic manifestation, characterized by a latency period of several weeks, with distal axonal degeneration and extensive involvement of the lower limbs.3,4 The detection of subclinical damage in the central nervous system may provide an early window to prevent severe symptomatic neuropathy.
Regarding this specific aspect, we must be especially careful when we affirm the existence of subclinical manifestations based on complementary exams, which need previous normative data, and sometimes independent serial exams, based on having exhausted specialized medical exams with the use of clinical scales.
In the article, it would have been interesting to complement the neurophysiologic investigation with studies of fine and sympathetic fibers, since one of the paradigms involves motor predominance in OP, but patients with OP usually present with gait ataxia and distal paresthesia.
Cases of potentially preventable polyneuropathy such as TN and especially those related to OP are not rare, and the article adds elements to an interdisciplinary theme. The authors concluded that OP may be avoided, and when diagnosed promptly, will be able to exhibit reversal of the evolution of the process, as seen in some cases.
We thank the authors for the excellent article that adds to the knowledge of a relevant topic
REFERENCES
1. Richardson KJ, Schwinck JL, Robinson MV. Organophosphate poisoning. Nurse Pract. 2021;46(7):18-21. [Context Link]
2. Karam C, Dyck PJ. Toxic neuropathies. Semin Neurol. 2015;35(4):448-457. [Context Link]
3. Hernandez-Fustes OJ, Arteaga-Rodriguez C, Ambrozewicz RA, De Marchi Assuncao C, Hernandez Fustes OJ, Feitosa A. Toxic polyneuropathy. Int J Neurol Brain Disord. 2019;7(1):1-3. [Context Link]
4. Ergun SS, Ozturk K, Su O, Gursoy EB, Ugurad I, Yuksel G. Delayed neuropathy due to organophosphate insecticide injection in an attempt to commit suicide. Hand (N Y). 2009;4(1):84-87. [Context Link]
-Otto Fustes, MD, MSc, PhD and Carlos Arteaga Rodriguez, MD, MSc
Response from authors
Thank you very much for your letter to the editor in response to our article on organophosphate poisoning. We greatly appreciate your comments regarding the seriousness of exposure and subsequent sequelae, both immediate and latent. This article was originally intended to be a case study sharing a patient encounter experienced by one of the authors. His singular complaint was of "lump on left chest that comes and goes." No lump was found on physical exam, but the patient revealed that he had lumps that come and go in other places, stating he had one in his arm. After having the patient remove his shirt, multiple scars were noted on his shoulders bilaterally as well as fasciculations in the forearm. When questioned about the source of the scars, the patient disclosed that he had a problem with bedbugs.
Further questioning revealed multiple pesticide treatments of the patient's apartment by his landlord in the month preceding his office visit and further treatments administered by the patient himself, using several cans of "bug spray" at each time. Had the provider not been familiar with signs and symptoms of organophosphate agents from her time as a military healthcare provider, it is very likely that this patient would have not been appropriately diagnosed or treated. Our hope is that this article, and your subsequent response, spurns dialog about exposure prevention, recognition of subclinical symptoms, acute treatment, and mitigation of long-term disability.
-Kathleen J. Richardson, DNP, ARNP, FNP-C, ENP-BC, CEN, FAEN; Jessica L. Schwinck, DNP, ARNP, AGACNP-BC, FNP-BC, ACCNS-AG, CWOCN, CEN; and Marylou V. Robinson, PhD, ARNP, FNP-C