Aquarism: an innocent leisure activity? Palytoxin-induced acute pneumonitis

Coral Keratitis: Case Report and Review of Mechanisms of Action, Clinical Management and Prognosis of Ocular Exposure to Palytoxin

Palytoxin is one of the most lethal natural toxins ever discovered. This molecule has been isolated from various marine animals, including zoanthid corals. This popular organism is commonly found in many home saltwater aquariums due to its beauty and survivability. As a result of an increase in popularity, an increased number of individuals are at risk for exposure to this potentially deadly toxin. Affected patients may experience various symptoms based on the route of exposure (ie, cutaneous contact, inhalation of aerosolized toxin, ocular exposure, or ingestion). Ocular exposure can occur in various ways (eg, contact with contaminated water, rubbing the eye with a dirtied hand, or direct spraying into the eye), and incidence rates have dramatically risen in recent years. In this review, we discuss a case of systemic toxicity from inhalation and ocular exposure to presumed palytoxin on a zoanthid coral which resulted in an intensive care unit (ICU) stay, and corneal perforation which required a corneal transplant. Additionally, we review what is known about the mechanism of action of this toxin, propose a comprehensive hypothesis of its effects on corneal cells, and discuss the prognosis and clinical management of patients with systemic symptoms secondary to other routes of exposure.

A case of long-term neurological and respiratory sequelae of inhalational exposure to palytoxin

Palytoxin has been found in several soft coral species which are popular for in-home reef aquariums. Although a limited number of case reports describing acute respiratory distress after inhalational exposure to palytoxin have been reported, there have been no reports regarding the potential long-term effects of inhalational exposure to palytoxin in the literature. This case follows an aquatic specialist in the U.S. over a period of seven years after a single intense occupational exposure to the aerosolized toxin from cleaning of a residential aquarium.

Human Poisoning from Marine Toxins: Unknowns for Optimal Consumer Protection

Marine biotoxins are produced by aquatic microorganisms and accumulate in shellfish or finfish following the food web. These toxins usually reach human consumers by ingestion of contaminated seafood, although other exposure routes like inhalation or contact have also been reported and may cause serious illness. This review shows the current data regarding the symptoms of acute intoxication for several toxin classes, including paralytic toxins, amnesic toxins, ciguatoxins, brevetoxins, tetrodotoxins, diarrheic toxins, azaspiracids and palytoxins. The information available about chronic toxicity and relative potency of different analogs within a toxin class are also reported. The gaps of toxicological knowledge that should be studied to improve human health protection are discussed. In general, gathering of epidemiological data in humans, chronic toxicity studies and exploring relative potency by oral administration are critical to minimize human health risks related to these toxin classes in the near future.

Prevalence and characteristics of inhalational and dermal palytoxin exposures reported to the National Poison Data System in the U.S

INTRODUCTION

Palytoxin, produced by unicellular microalgae, is one of the most potent toxins known. Human exposure results most prominently through oral, dermal, and inhalational contact. There is no current data on the prevalence of cases in the United States.

METHODS

This study reviewed human inhalational and dermal exposures to palytoxin via records from the National Poison Data System from 2000 to 2014.

RESULTS

There were 171 cases reported, the majority occurred at a residence and experienced minor respiratory or dermal symptoms and recovered without any major sequelae or fatalities. Ten patients required admission to an intensive care unit.

CONCLUSION

The incidence of palytoxin exposure is low but significant symptoms can occur.

Palytoxin-induced acute respiratory failure

Palytoxin is one of the most potent toxins known to mankind and poses a high risk to humans through ingestion, inhalation and dermal routes [1,2]. Although the exact mechanism of action is unknown it is postulated that palytoxin binds to the Na+/K + ATPase pump resulting in K⁺ efflux, Ca²⁺ influx and membrane depolarization leading to widespread secondary pharmacological actions [2]. Palytoxin is highly toxic and can affect multiple organs causing severe symptoms including death. Palytoxin poisoning is mainly developed after ingesting seafood. We are reporting a case of suspected inhalational palytoxin poisoning in a healthy healthcare provider from who developed severe respiratory distress within 12 hours of exposure to vapors. We have highlighted diagnostic clues and clinical features in the patients' history that may help intensivists to diagnose a case of ARDS secondary to palytoxin poisoning.

Palytoxin-Containing Aquarium Soft Corals as an Emerging Sanitary Problem

Palytoxin (PLTX), one the most potent marine toxins, and/or its analogs, have been identified in different marine organisms, such as Palythoa soft corals, Ostreopsis dinoflagellates, and Trichodesmium cyanobacteria. Although the main concern for human health is PLTXs entrance in the human food chain, there is growing evidence of adverse effects associated with inhalational, cutaneous, and/or ocular exposure to aquarium soft corals contaminated by PLTXs or aquaria waters. Indeed, the number of case reports describing human poisonings after handling these cnidarians is continuously increasing. In general, the signs and symptoms involve mainly the respiratory (rhinorrhea and coughing), skeletomuscular (myalgia, weakness, spasms), cardiovascular (electrocardiogram alterations), gastrointestinal (nausea), and nervous (paresthesia, ataxia, tremors) systems or apparates. The widespread phenomenon, the entity of the signs and symptoms of poisoning and the lack of control in the trade of corals as aquaria decorative elements led to consider these poisonings an emerging sanitary problem. This review summarizes literature data on human poisonings due to, or ascribed to, PLTX-containing soft corals, focusing on the different PLTX congeners identified in these organisms and their toxic potential.

Determination of Palytoxins in Soft Coral and Seawater from a Home Aquarium. Comparison between Palythoa- and Ostreopsis-Related Inhalatory Poisonings

Anecdotal reports exist of aquarium hobbyists that experienced severe respiratory distress and/or skin injury following cleaning operation of home aquaria containing Palythoa sp. soft corals. Hundreds of cases of respiratory illness and/or dermatitis have been recorded in proximity to the sea concomitantly with algal blooms of Ostreopsis spp. in the Mediterranean area. Both Palythoa spp. and Ostreopsis spp. contain congeners of palytoxin, a highly potent toxin whose inhalation hazard is however unknown. In this study, we demonstrate the presence of high levels of palytoxins (palytoxin and hydroxypalytoxin) in both soft coral and seawater from a home marine aquarium involved in the poisoning of a whole family. Due to the high toxin levels found in seawater, a procedure for a rapid and efficient determination of palytoxin in seawater was setup. A comparison of symptoms of Palythoa- and Ostreopsis-related inhalatory poisonings showed many similarities including fever, respiratory distress, nausea, and flu-like symptoms. From the chemical and symptomatological data reported herein it is reasonable to hold palytoxins responsible for respiratory disorders following inhalation. Although the exact mechanism through which palytoxin congeners exert their inhalatory toxicity is still unknown, this represents a step toward demonstrating that palytoxin congeners exert toxic effects through inhalation both in natural environments and in the surroundings of private and public aquaria.

A Case of Palytoxin Poisoning in a Home Aquarium Enthusiast and His Family

Inhalational exposure to palytoxin is an extremely rare cause of respiratory distress. This little-known marine toxin has the potential to cause significant morbidity and mortality. Toxicity has been best documented in cases of ingestion but has also been seen in cases of dermal exposure and inhalation of vapors. Palytoxin has been found in several coral species, some of which are favored by home aquarium enthusiasts and are commercially available. We report a case of a family who were exposed to the aerosolized toxin following the cleaning of a coral in their home aquarium. It is important that clinicians be aware of this source of toxic exposure to provide necessary care to these patients.