RADS after exposure to a riot-control agent: a case report

Tear gas: an epidemiological and mechanistic reassessment

Deployments of tear gas and pepper spray have rapidly increased worldwide. Large amounts of tear gas have been used in densely populated cities, including Cairo, Istanbul, Rio de Janeiro, Manama (Bahrain), and Hong Kong. In the United States, tear gas was used extensively during recent riots in Ferguson, Missouri. Whereas tear gas deployment systems have rapidly improved-with aerial drone systems tested and requested by law enforcement-epidemiological and mechanistic research have lagged behind and have received little attention. Case studies and recent epidemiological studies revealed that tear gas agents can cause lung, cutaneous, and ocular injuries, with individuals affected by chronic morbidities at high risk for complications. Mechanistic studies identified the ion channels TRPV1 and TRPA1 as targets of capsaicin in pepper spray, and of the tear gas agents chloroacetophenone, CS, and CR. TRPV1 and TRPA1 localize to pain-sensing peripheral sensory neurons and have been linked to acute and chronic pain, cough, asthma, lung injury, dermatitis, itch, and neurodegeneration. In animal models, transient receptor potential inhibitors show promising effects as potential countermeasures against tear gas injuries. On the basis of the available data, a reassessment of the health risks of tear gas exposures in the civilian population is advised, and development of new countermeasures is proposed.

Exposure to the riot control agent CS and potential health effects: a systematic review of the evidence

o-Chlorobenzylidene malononitrile (CS) is one of the most extensively used riot control agents. Our aim was to conduct a systematic review of the potential health effects related to CS exposure. We searched for papers in English between 1991 and 2014. Thirty five (35) studies (25 case reports, seven descriptive studies and three analytical studies) were included in the review. In the twenty five case reports/series 90 cases of exposure to CS and their clinical effects are presented. Their mean age was 25.7 years and 62.0% were males. In addition, 61% of the cases described dermal, 40% respiratory, 57% ocular clinical effects. Life threatening situations as well as long-term health effects were found and were related with exposure to confined/enclosed space. Descriptive and analytical studies have shown attack rates ranging from 12% to 40%. Subjects who were sprayed by the police more often needed special treatment and reported adverse health effects. Apart from transient clinical effects, CS could have lasting and serious effects on human health. Better surveillance of the subjects exposed to CS and completion of cohort studies among exposed populations will illuminate the spectrum of the health effects of exposure to CS.

The pathology of lethal exposure to the Riot Control Agents: towards a forensics-based methodology for determining misuse

The aim of this is to review deaths associated with the use of Riot Control Agents (RCAs) and to assess how the presenting pathologies is such cases may better inform cause of death conclusions upon autopsy. We also sought to present which additional steps should be added to the Minnesota protocol and the European harmonization of medico-legal autopsy rules in suspected cases of deaths associated with the use of RCAs. We included 10 lethal cases in our study. In three cases, RCAs were found to be the sole cause of death, in three cases RCAs were ruled a secondary cause of death due asphyxia or asthma subsequent to exposure to RCAs and in four cases RCAs were contributory factors to death. In three cases the responsible agents were identified as Chloroacetophenone (CN), Chlorobenzylidene malononitrile (CS) and Oleoresin capsicum (OC) and in the remaining 7 cases, the agent was OC alone. As there are no specific findings in suspected cases of death associated with RCA use, establishing cause of death and whether RCAs are the sole cause or only a contributory factor will be based on the elimination of other possible causes of death. For this reason, a specifically structured autopsy is essential. This specifically structured autopsy should contain basic principles of the Minnesota Protocol and the European harmonization of medico-legal autopsy rules with the following additional steps taken: examination of clothing, eyes, and skin; examination of pharyngeal, tracheobronchial, and eusophegeal mucosas; and a thorough recording of the steps taken by the party conducting the arrest, including other possible causes of in-custody death, as well as a detailed medical history of the deceased.

Cayenne aspiration: an unusual type of lower airway foreign-body aspiration

Purpose

Cayenne aspiration is an unusual type of foreign-body aspiration that is usually misdiagnosed. This article analyzes the clinical features of cayenne aspiration in the lower airway.

Patients and methods

Clinical data on eight adult patients with cayenne aspiration were retrospectively analyzed. Six were elderly patients. The data were collected from Peking University First Hospital and Anhui Chest Hospital between January 2010 and August 2014.

Results

The most common symptoms of cayenne aspiration were cough (eight cases, 100%) and sputum (five cases, 62.5%). Only one patient (12.5%) could supply the history of aspiration on his first visit to doctor and was diagnosed definitely without delay. The other seven cases were misdiagnosed as pneumonia and the time to accurate diagnosis was from 1 month to 6 months. The history of aspiration could be recalled after confirmed diagnosis for the other seven cases. The most common presentation shown by chest computed tomography (CT) was pneumonic opacity (eight cases, 100%). The existence of cayenne could not be detected by chest CT in any of the patients. All the patients were diagnosed definitively and managed successfully with flexible bronchoscopy. Cayenne was more often lodged in the right bronchus tree (seven cases, 87.5%), especially the right lower bronchus (four cases, 50%). The segment of cayenne was complete in five cases (62.5%) and scattered in three cases (37.5%).

Conclusion

The clinical features of cayenne aspiration are usually obscure and nonspecific which may lead to delay in diagnosis. Flexible bronchoscopy is safe and useful for early diagnosis and effective management.

Safety of capsaicin cough challenge testing

BACKGROUND

Capsaicin, the pungent extract of red peppers, has achieved widespread use in clinical research because it induces cough in a dose-dependent and reproducible manner. Although > 2 decades of experience has led investigators to consider capsaicin cough challenge testing a safe diagnostic modality, this issue has not been specifically addressed in the literature.

STUDY OBJECTIVES

To review the published experience with capsaicin inhalation challenge testing in terms of safety.

DESIGN

Literature review and personal communication with study authors.

SETTING

Academic medical center.

RESULTS

One hundred twenty-two published studies since 1984 described 4,833 subjects (4,374 adults, 459 children) undergoing capsaicin cough challenge, with no serious adverse events reported. Subjects included healthy volunteers as well as patients with asthma, COPD, pathologic cough, and other respiratory conditions. Minor complaints described in a small fraction of studies consisted mainly of transient throat irritation. Personal communication with the authors of > 90% of the studies confirmed an absence of any serious adverse events. Furthermore, these investigators have performed thousands of additional capsaicin challenge studies not reported in the literature, also without any associated serious adverse events.

CONCLUSIONS

A review of the 20-year clinical experience has failed to uncover a single serious adverse event associated with capsaicin cough challenge testing in humans. Given the need for better antitussive therapies, capsaicin represents a vital component of future scientific inquiry in the field of cough.

Medical hazards of the tear gas CS. A case of persistent, multisystem, hypersensitivity reaction and review of the literature

A 30-year-old incarcerated man was sprayed with the "tear gas" ortho-chlorobenzylidene malononitrile (CS). He was hospitalized 8 days later with erythroderma, wheezing, pneumonitis with hypoxemia, hepatitis with jaundice, and hypereosinophilia. During the subsequent months he continued to suffer from generalized dermatitis, recurrent cough and wheezing consistent with reactive airways dysfunction syndrome, and eosinophilia. These abnormalities responded to brief courses of systemic corticosteroid but recurred off therapy. The dermatitis resolved gradually over 6-7 months, but the patient still had asthma-like symptoms a year following exposure. Patch testing confirmed sensitization to CS. The mechanism of the patient's prolonged reaction is unknown but may involve cell-mediated hypersensitivity, perhaps to adducts of CS (or a metabolite) and tissue proteins. This is the first documented case in which CS apparently caused a severe, multisystem illness by hypersensitivity rather than direct tissue toxicity. Both the ethics and safety of CS use remain controversial, in part because of the difficulty documenting sporadic injuries received in the field, and also because the charged circumstances surrounding CS use may lead to both underreporting and exaggerated claims of medical harm. The medical literature on CS focuses mainly on its immediate irritant effects and on transient dermal and ocular injuries, with only 2 prior case reports of acute lung injury related to CS exposure. Given the paucity of documented lasting effects despite its widespread use for more than 3 decades, CS appears to be safe when deployed (outdoors) in a controlled manner, but it can cause important injuries if misused or if applied to a sensitized individual.