Bedbugs: An old problem with a new dimension

Bed bugs: clinical relevance and control options

Since the late 1990s, bed bugs of the species Cimex lectularius and Cimex hemipterus have undergone a worldwide resurgence. These bed bugs are blood-sucking insects that readily bite humans. Cutaneous reactions may occur and can start out as small macular lesions that can develop into distinctive wheals of around 5 cm in diameter, which are accompanied by intense itching. Occasionally, bullous eruptions may result. If bed bugs are numerous, the patient can present with widespread urticaria or eythematous rashes. Often, bites occur in lines along the limbs. Over 40 pathogens have been detected in bed bugs, but there is no definitive evidence that they transmit any disease-causing organisms to humans. Anemia may result when bed bugs are numerous, and their allergens can trigger asthmatic reactions. The misuse of chemicals and other technologies for controlling bed bugs has the potential to have a deleterious impact on human health, while the insect itself can be the cause of significant psychological trauma. The control of bed bugs is challenging and should encompass a multidisciplinary approach utilizing nonchemical means of control and the judicious use of insecticides. For accommodation providers, risk management procedures should be implemented to reduce the potential of bed bug infestations.

Patients with papular urticaria have IgG antibodies to bedbug (Cimex lectularius) antigens

IgG and IgE against salivary gland proteins of bedbug (Cimex lectularius) were assessed in comparison with mosquito (Culex pipiens) and flea (Pulex irritans) antigens in the sera of papular urticaria patients (group I), siblings without papular urticaria (group IIa), patients' parents (group IIb), and healthy controls (group III) (Immunoblotting). Anti-C. lectularius IgG was significantly recognized at 66 and 10 kDa in 40% of group I, besides others ranging from 45 to 107 kDa. Group IIa significantly reacted with 70 kDa (57.1%). Group IIb reacted with 21 and 8.5 kDa (26.7%). Sixty percent of group IIb and 100% of group III significantly identified a band of 12.5 kDa. IgG against C. pipiens was significantly recognized at a range of 18-105 kDa in group I, IIb (115, 7 kDa), and III (58, 50 kDa). Anti-P. irritans IgG was significantly recognized by group I (100, 70 kDa) and group IIa (60, 35 kDa). IgE response was confined to C. pipiens at 115 and 54 kDa in groups I and III, respectively, besides 68 and 58 kDa in group IIa. It is concluded that IgG is present against C. lectularius, C. pipiens, and P. irritans in papular urticaria and may contribute to its pathogenesis.

The return of the common bedbug

The incidence of skin disease secondary to infestation with the human bedbug, Cimex lectularius, has increased dramatically in the United States and in the United Kingdom. We describe a child with a recurrent pruritic eruption of urticarial, erythematous papules on the face, neck, and extremities. The etiology of her cutaneous lesions was discovered to be a bedbug infestation in the home. The epidemiology, entomology, presentation, and treatment of bedbugs and their bites are discussed.

Arthropods in dermatology

Arthropods are important in medicine for a multitude of reasons. Their bites and stings may induce allergic reactions, ranging from annoying to life-threatening. Many arthropod products are also capable of inciting allergic responses in sensitized persons. In recent years, bites and stings have gained greater attention owing to increased concern about disease transmission. A common hypersensitivity response to arthropod bites, stings, and products is papular urticaria. This eruption occurs primarily in children, who eventually "outgrow" this disease, probably through desensitization after multiple arthropod exposures. Papular urticaria is most often caused by fleas or bedbugs, but virtually any arthropod is capable of inducing such a reaction. Two arthropod classes of medical importance are the Arachnida (spiders, scorpions, ticks, and mites) and the Insecta (lice, fleas, bedbugs, flies, bees, and ants). Animals in these two classes are probably responsible for more morbidity and mortality worldwide than are any other group of venomous creatures. In general, the diagnosis of arthropod bites and stings is dependent on maintenance of a high index of suspicion and familiarity with the arthropod fauna not only in one's region of practice, but also in the travel regions of one's patients. Learning objective At the completion of this learning activity, participants should be familiar with the clinical manifestations caused by a variety of arthropods as well as the treatment and possible sequelae of arthropod attacks.