Tungiasis is a parasitic disease resulting from infestation by a female flea Tunga penetrans. The parasites are endemic in the tropics and can infect patients with diabetes mellitus (DM). Augmented by uncontrolled hyperglycemia and pre-existing neuropathy, the parasite may trigger a locally spreading inflammation, which may aggravate the trauma introduced during its extraction, leading into a rapidly progressing foot ulcer. To the best of our knowledge, no such cases in patients with type 2 diabetes have ever been published from Tanzania and likely none worldwide. This case report shows that, in diabetic patients, the wound resulting from the extraction of T. penetrans may get infected and aggravated by the ongoing inflammatory reaction, rapidly evolve into limb-threatening condition and mortality. Preventive measures are necessary and should be emphasized in patients with DM. Studies are needed to increase our understanding of the pathophysiology, proper management and sequalae of ulcers of this nature.