Severe Iron Deficiency Anaemia Caused by bed bug Parasitisation without a Rash

Bed bugs (Cimex lectularius) are blood-sucking insects widely distributed in temperate regions. While they are not known to be vectors of infectious diseases, their bites often cause dermatological symptoms, such as pruritus and rash. Rarely, chronic infestations may lead to systemic complications, including iron deficiency anaemia. Only a few case reports, most involving individuals with reduced activities of daily living (ADL) or social isolation, have described this association.

We report herein the case of an 82-year-old woman in whom a chronic bed bug infestation caused severe iron deficiency anaemia without skin symptoms. She presented nearly complete dependence in her ADL. On admission, her haemoglobin level was 2.7 g/dl, and the other, laboratory findings indicated iron deficiency anaemia. Various examinations excluded malignancy, haematological disease, and other sources of blood loss. Numerous bed bugs were observed on her body and clothing. Following a blood transfusion, iron supplementation, and eradication of the infestation through repeated bathing, her haemoglobin level improved. Thereafter, the anaemia did not recur. She was later transferred to a special nursing home, as eradication of the insects in her home was not feasible.

This case illustrates that elderly individuals whose living environment is chronically infested by bed bugs can experience severe iron deficiency anaemia even in the absence of bite marks on the skin. A careful, physical examination and inspection of clothing and the living environment are crucial for diagnosis. Clinicians should consider bed bug bites as a potential cause of unexplained anaemia, particularly in older patients with reduced ADL.

Iron deficiency anaemia may develop in elderly patients, particularly those with decreased activities of daily living or social isolation, if their living environment is chronically infested by bed bugs.Bed bug bites do not always present skin symptoms, as repeated exposure may lead to desensitization and an attenuated cutaneous reaction, especially in older adults.Careful history-taking and a thorough physical examination, including inspection of the patient's clothing and living environment, are essential to determine if bed bugs are the cause of otherwise unexplainable anaemia.