A prognostic score to identify low-risk outpatients with acute deep vein thrombosis in the lower limbs

BACKGROUND

No prior studies have identified which patients with deep vein thrombosis in the lower limbs are at a low risk for adverse events within the first week of therapy.

METHODS

We used data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) to identify patients at low risk for the composite outcome of pulmonary embolism, major bleeding, or death within the first week. We built a prognostic score and compared it with the decision to treat patients at home.

RESULTS

As of December 2013, 15,280 outpatients with deep vein thrombosis had been enrolled. Overall, 5164 patients (34%) were treated at home. Of these, 12 (0.23%) had pulmonary embolism, 8 (0.15%) bled, and 4 (0.08%) died. On multivariable analysis, chronic heart failure, recent immobility, recent bleeding, cancer, renal insufficiency, and abnormal platelet count independently predicted the risk for the composite outcome. Among 11,430 patients (75%) considered to be at low risk, 15 (0.13%) suffered pulmonary embolism, 22 (0.19%) bled, and 8 (0.07%) died. The C-statistic was 0.61 (95% confidence interval [CI], 0.57-0.65) for the decision to treat patients at home and 0.76 (95% CI, 0.72-0.79) for the score (P = .003). Net reclassification improvement was 41% (P < .001). Integrated discrimination improvement was 0.034 for the score and 0.015 for the clinical decision (P < .001).

CONCLUSIONS

Using 6 easily available variables, we identified outpatients with deep vein thrombosis at low risk for adverse events within the first week. These data may help to safely treat more patients at home. This score, however, should be validated.

Hyperhidrosis related to nevirapine therapy

A 70-year-old white man presented to the internal medicine outpatient clinic with symptoms of significant hyperhidrosis. He had been started on antiretroviral therapy (ART) with tenofovir, lamivudine and nevirapine. The patient complained of excessive sweating following severe asthenia after taking nevirapine. Based on these findings, we suspected that the causative agent was nevirapine and a diagnosis of hyperhidrosis due to nevirapine was made. Nevirapine treatment was stopped and was substituted with efavirenz: the patient continued on therapy with tenofovir and lamivudine. The hyperhidrosis symptoms resolved in 2-3 days. No relapse was observed with the new ART regimen. Drugs that induce hyperhidrosis can cause patient discomfort and embarrassment. In our patient, this adverse drug reaction also caused severe asthenia that decreased the patient's physical and emotional quality of life. There was a temporal relationship between the developments of symptoms and starting nevirapine therapy. Once nevirapine was suspended and switched to efavirenz, excessive sweating resolved. An objective causality assessment revealed that the adverse effect was probable. Until further data are available, clinicians should consider discontinuation of nevirapine therapy in patients who develop severe hyperhidrosis.