Lesions caused by arthropods

Crustaceans belonging to the Arthropod class are present in both fresh and saltwater. These animals, such as crabs and lobsters, for instance, have a solid carapace and are armed with two strong claws that end in pincers. Thanks to their mechanical devices, Crustaceans do not need chemical weapons to capture the prey or to defend themselves from predators. Even if they do not produce toxins they can, however, induce traumatic-lacerating wounds with their claws. In lobster catchers a dermatitis of the hands can be observed, featuring pruriginous manifestations, complicated by hypercheratosis and ragade-like cracks. Secondary infection is a concern in bites and cutting wounds caused by Crustaceans. It should also be borne in mind that these animals are one of the most prevalent causes of food allergy worldwide: the muscle protein, tropomyosin, is the major allergen in shrimps and is also present in Mollusks and Arthropods. Tropomyosin is notorious as a cross-reactive pan-allergen; as a consequence, patients who are allergic to Crustaceans can also show a clinical reaction to Mollusks and mites. Barnacles, or cirripedia, sessile animals covered with a calcareous shell with sharp edges, also cause cutting wounds of variable severity; they colonize hard substrates (quays, buoys, the hulls of ships, harbor bottoms) in particularly polluted waters.