Allergy-associated diseases have a multitude of confirmed or suspected etiologies and associations affecting organs and organ systems. The hyper-reactivity of the immune system in which the eosinophils are prominent plays a central role in organ-specific and systemic effects in these diseases. Patients may be plagued with nonspecific, episodic, or progressive signs and symptoms. Patients may also exhibit signs and symptoms that mimic more common conditions. Recognition of certain patterns of clinical signs and symptoms may lead to definitive clinical diagnosis and effective treatment, particularly of less common but potentially lethal disease entities. The lack of clinical recognition of these patterns, whether due to “red herring” historical information, lack of sign/symptom specificity, clinical presentation at early stage, or unfamiliarity with the constellation of disease presentation, may delay or preclude diagnosis and treatment. The forensic pathologist must also have an awareness of varied clinical presentations of diseases because these can provide us with direction toward the ultimate determination of cause and manner of death.The importance and contribution of the practice of forensic pathology are highlighted in the instance of sudden and unexpected death, whereby the previously unrecognized or unconfirmed disease entity that leads to the death is revealed via analysis of scene information, autopsy performance, and review of medical history and history of the most recent illness. Through this comprehensive approach, a greater understanding of the extent and potential lethality of disease with reiteration of the importance of early clinical diagnosis and treatment is reinforced. This benefits the medical community involved in diagnosis and treatment, clinicians and pathologists alike, with the ultimate goal of reduction of morbidity and mortality.Reported is a case of sudden unexpected death with historical, gross, and microscopic findings consistent with a multisystem, inflammatory, allergic disease entity.