Blastocystis hominis associated acute urticaria.

Acute urticaria has many causative factors, which may include infections, medications (nonsteroidal anti-inflammatory drugs, antibiotics, contraceptives and others), insect bites, physical stimuli, allergens or underlying systemic disorders. Blastocystis spp, although ubiquitous in developing countries, is rarely implicated in causing disease in the developed world. The authors present a case of acute urticaria caused by Blastocystis hominis (protozoon parasite) in an elderly farmer in rural United States.

DDAVP-associated hyponatremia.

More than 250,000 patients with nocturnal enuresis have been treated with DDAVP in the United States since 1989. It adequately controls nocturnal enuresis in over half of patients with significant improvement in their quality of life. Although the overall incidence of adverse effects associated with treatment of nocturnal enuresis with DDAVP is low, it is not a benign drug particularly when used in patients at extreme of age.