Recrudescent herpes simplex infection mimicking primary herpetic gingivostomatitis

Recrudescent herpes simplex infection mimicking primary herpetic gingivostomatitis

1462 CURRENT LITERATURE Reprint requests to Dr Cheung: Department of Oral and Maxlllofacial Surgery, University of Hong Kong, Hong Kong. Heparin-In...

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1462

CURRENT LITERATURE

Reprint requests to Dr Cheung: Department of Oral and Maxlllofacial Surgery, University of Hong Kong, Hong Kong.

Heparin-Induced Thrombocytopenia. Warkentin TE. Postgrad Med 103:169, 1998

Kelton

JG,

The indications for heparin therapy are increasing and the incidence of heparin-induced thrombocytopenia (HIT) is also increasing. Nevertheless, the risk of thrombotic complications from no therapy is far greater than the bleeding risk from therapy. Although the risk is dose-dependent, any heparin preparation at any dose can induce this reaction. Although few reported reactions can be found where patients developed serious bleeding; patients can develop outcomes that lead to amputation, myocardial infarction, or stroke. In this article, the author reviews the indications, risks, signs and symptoms, causes, and alternative therapies that can be used in management of such patients. HIT typically occurs 5 to 15 days into heparin therapy, but can occur sooner. It can also occur several days after heparin discontinuance (delayed-onset HIT). The risk is dosedependent, with the highest risk being when heparin is given in full, therapeutic doses. In one study, the risk of HIT at intermediate heparin doses (7,500 units twice a day) was reportedly 2.8%. HIT risk is greater when using bovine heparin than porcine, and for orthopedic surgery patients than general medical patients. Typical platelet counts in cases of HIT range from 2,500 to lO,OOO/mL. Clinical diagnosis is difficult. The best standard measure available today is the serotonin-release assay, which measures heparindependent platelet release from washed platelets at two heparin concentrations. However, this test is difficult to perform so it is not widely used. Other studies can give false positive and negative results in up to 10% of tested patients. The pathophysiology of HIT shows that patients who are exposed to heparin form antibodies against a resulting heparin-platelet complex. About one third of of those become thrombocytopenic. Treatment also consists of knowing which patients to treat. Among the alternative drugs discussed are Ancrod (a snake venom extract), low molecular weight heparin, thrombin-specific inhibitors such as argatroban and hirudin, antiplatelet therapies, and oral anticoagulants. Vena cava interruption can also be used for patients for whom there is no readily available alternative antithrombotic agent. Patient who have HIT without associated or underlying thrombosis represent the largest population with HIT, but isolated HIT can progress to a thrombotic complication after discontinuance of heparin-ROGER E. ALEXANDER Reprint requests to Dr Kelton: McMaster University Medical Centre, 1200 Main St W, HSC-3X28, Hamilton, Ontario, Canada LSN 325.

was sampled at initial presentation and again at follow-up (10 to 14 days later). Indirect immunoflorescence was used to detect HSV specific immunoglobulin G (IgG) and immunoglobulin M (IgM) in the sampled sera. Results of sera taken from study patients at initial presentation found the presence of HSV specific IgG and an absence HSV specific IgM. In each patient the titre of anti-HSV IgG rose at least fourfold between initial and convalescent sera and all convalescent sera became positive for anti-HSV IgM. The presence of anti-HSV IgG and the absence of anti-HSV IgM in initial sera suggests prior exposure to HSV and confirms that these patients were exhibiting a secondary HSV infection. Further suggesting that the presentation of primary herpetic gingivostomatitis in these patients was, in fact, a recrudescent HSV infection mimicking a primary presentation.-R.J. LESNY Reprint requests to Dr Christie: Regional Virus Laboratory, Royal Group of Hospitals and School of Clinical Dentistry, Queen’s University of Belfast, Belfast, Northern Ireland.

The The

Induced Hypotension May Influence Blood Loss in orthognathic Surgery, but it is Not Crucial. Enlund MG, Ahlstedt BL, Andersson LG, et al. Stand J Plast Reconstr Hand Surg 31:311, 1997 The authors evaluate the benefit of induced hypotension during orthognathic surgery. Blood loss, duration of procedure, surgeon’s judgement of surgical field, and final operative results were compared between patients undergoing induced hypotension (mean arterial pressure = 50 to 64 mm Hg) versus normotension (mean arterial pressure 2 65 mm Hg). Forty patients were randomly assigned to either the hypotension or normotension group during orthognathic procedures. Isoflurane anesthetic technique was used for establishing appropriate pressure range (radial artery) for both groups. Blood loss and rate of loss were measured, and two visual analogue scales were designed for surgeons to 1) estimate blood loss and 2) describe surgical field quality. Surgeons were blind to which anesthetic technique was used for each patient. Although there was a significant difference with rate of bleeding (mean rates = 0.9 mL/min [hypotension] vs 1.8 mL/min [normotension]), there was not a significant difference in total blood loss. Final results (6 months postoperatively) and duration of procedures did not differ significantly between the two groups. Surgeons did not detect significant differences in blood loss or surgical field quality. Together with the other results, the authors believe a mean reduction of 150 mL blood loss with induced hypotension does not provide enough support to continue using induced hypotension during orthognathic surgery.-K. BENSON Reprint requests Intensive

to Dr Enlund: Department of Auaesthesia Care, Central Hospital, Vasteras, Sweden.

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Recrudescent Herpes Simplex Infection Mimicking Primary Herpetic Gingivostomatitis. Christie SN, McCaughey C, Marley JJ, et al. J Oral Path01 Med 27:8, 1998

Laser Physics and Physiology. Surg 25:89, 1998

Herpes simplex virus (HSV) infection results in three well-known sequela stemming from reactivation of latent HSV, specitlcally, recurrent herpes labialis, asymptomatic shedding of herpes virus, and localized intraoral recrudescence. The authors suggest a fourth sequela, recrudescent intraoral herpes simplex infection, that mimics primary herpetic gingivostomatitis. The authors studied six patients who presented within 2 to 4 days of developing panoral ulcerations of both keratinized and nonkeratinized mucosa, mild pyrexia, and cervical lymphadenopathy. Venous blood

The laser transforms electrical energy to light energy. The light energy then is applied to tissue to accomplish a task. Lasers consist of the following three basic components: a power source, a lasing medium consisting of molecules or atoms that store and release energy, and reflecting mirrors that return the photons to the lasing medium until they are released from the laser in the form of laser energy. Laser energy, although commonly referred to as light, can be invisible to the human eye (400 nm to 700 nm). Laser light is considered disciplined light in contrast to most other light

Gregory

RO. Clin Plast