1/2. A patient with severe black fly (simuliidae) hypersensitivity referred for evaluation of suspected immunodeficiency.BACKGROUND: Biting flies of the diptera order and specifically the black fly (simuliidae family) can be rare causes of severe hypersensitivity reactions. OBJECTIVE: To describe a patient referred for evaluation of immunodeficiency whose clinical course is explained by severe simuliidae hypersensitivity. methods: The patient's immune system was investigated using standard laboratory evaluations. hypersensitivity to simuliidae was pursued because of historical features of her presentation and was specifically examined by skin prick and intradermal testing with whole body extract. RESULTS: The patient's history was notable for recurrent and severe seasonal episodes of presumed cellulitis after black fly bites that responded poorly to intravenous antibiotics. One episode was followed by acute inflammatory demyelinating polyneuropathy (guillain-barre syndrome) and another by minimal change nephrotic syndrome. The results of immunologic investigations were unremarkable, but cutaneous hypersensitivity to simuliidae was demonstrated with a 6.5-mm wheel and 35-mm flare reaction to intradermal injection of only 0.0005 microg of whole body extract. CONCLUSION: Similar to hymenoptera, simuliidae can rarely result in extreme hypersensitivity and should be considered in appropriate cases. This patient illustrates how severe reactions toinsect bites can be misdiagnosed.- - - - - - - - - - ranking = 1keywords = black (Clic here for more details about this article) |
2/2. Value of non-invasive continuous blood pressure monitoring in the detection of carotid sinus hypersensitivity.A patient with recurrent episodes of dizziness and blackouts is described. Detailed cardiac and neurological investigations were normal. Autonomic assessment excluded postural hypotension and confirmed normal sympathetic vasoconstrictor function. Cardiac parasympathetic function in response to deep breathing, hyperventilation and ocular pressure was normal. Left carotid sinus massage only reproducibly lowered blood pressure with minimal change in heart rate. This occurred mainly during head-up tilt. The fall in blood pressure was not affected by the muscarinic blocker atropine, or the peptide release inhibitor, octreotide. A diagnosis of left carotid sinus hypersensitivity of the vasodepressor variety was made. Left carotid sinus denervation was performed. This successfully prevented further episodes of dizziness and blackouts. The ability to measure beat-to-beat blood pressure non-invasively was of particular importance in diagnosis, and in the assessment of management options in this patient.- - - - - - - - - - ranking = 0.33333333333333keywords = black (Clic here for more details about this article) |