Clinical Information @ Emory

2/19/09

This blog has moved

Please visit the new location at http://www.healthlibrary.emory.edu/blogs/clininfo

1/30/09

What is the current state of diagnosing and managing heparin-induced thrombocytopenia (HIT)?

References
Review - Arepally GM, Ortel TL. Clinical practice. Heparin-induced thrombocytopenia. N Engl J Med. 2006 Aug 24;355(8):809-17.
Guidelines - Warkentin TE. Treatment and prevention of heparin-induced thrombocytopenia: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6 Suppl): 340S-380S.

1/29/09

What is the diagnostic or prognostic significance of measuring troponin and BNP levels in the setting of pulmonary embolism?

BNP

Reference
Cavallazzi R, et al. Natriuretic peptides in acute pulmonary embolism: a systematic review. Intensive Care Med. 2008 Dec;34(12):2147-56.
Full-text

Objective
Evaluate the available evidence on (a) the accuracy of BNP for the diagnosis of right ventricular dysfunction and (b) value as a prognostic factor of all-cause in-hospital or short-term mortality in patients with PE

Particulars
16 studies were included in this review; 14 studies addressed BNP in the setting of PE. N of these studies ranged from 17 to 124.

Data
Fig. 3 in the article shows that for BNP cutoff level of 100 pg/ml, the pooled odds ratio for all-cause in-hospital mortality was 6.00

Troponin

Reference
Becattini C, et al. Prognostic value of troponins in acute pulmonary embolism: a meta-analysis. Circulation. 2007 Jul 24;116(4):427-33.
Full-text

Objective
To determine if elevated serum troponin levels identify patients with acute pulmonary embolism at high risk of short-term mortality or adverse outcome.

Particulars
20 studies (4 retrospective) were included in this review

Data
Results were consistent for troponin I or T and prospective or retrospective studies.
In patients with elevated troponin levels...

Odds Ratio (OR) for short-term mortality = 5.24 (95% CI, 3.28 to 8.38)
OR for death resulting from pulmonary embolism = 9.44 (95% CI, 4.14 to 21.49)
OR for adverse outcome events* = 7.03 (95% CI, 2.42 to 20.43)

*NOTE: Adverse outcome events were defined differently in the studies, but authors chose to pool data because all studies aimed to identify patients experiencing "in-hospital clinical deterioration."

Is Homans sign a clinically significant in screening for deep vein thromboembolism?

Reference
Anand SS, et al. Does this patient have deep vein thrombosis? JAMA. 1998;279:1094-1099. Full-text

Objective
To review the validity of the clinical assessment and diagnostic tests in patients with suspected deep vein thrombosis

Particulars
Reviewed 68 studies dealing with the diagnosis of DVT; selected 5 studies that dealt with the relationship between clinical findings and venographic confirmation of DVT

Data
Table 2. Frequency of Symptoms and Signs in Patients with Suspected DVT

Results of 3 studies show that patients with and without DVT (confirmed with venography) could have a positive Homan’s sign as shown in Table 2.

1/15/09

Is long-term treatment with clopidogrel recommended for patients with acute coronary syndrome?

The 2007 ACC/AHA guidelines on managing patients with unstable angina/non–ST-elevation myocardial infarction recommend that clopidogrel be continued for up to twelve months. See summary chart in Section 5.2.1

For patients with gastrointestinal bleeding, how do you decide which patients to send to the floor & which to send to the ICU?

BLEED tool
Kollef MH, et al. BLEED: a classification tool to predict outcomes in patients with
acute upper and lower gastrointestinal hemorrhage. Crit Care Med. 1997 Jul;25(7):
1125-32.

How much of the small bowel can be seen during enteroscopy?

The adult small bowel is about 6 m in length. The technique push enteroscopy uses instruments in the range of 220 to 250 cm but usually only about 150 cm of small bowel can be seen. (Evaluation of obscure gastrointestinal bleeding. UptoDate. 2008.)

Another procedure is Sonde enteroscopy. A fiberoptic cable allows observation of 50-75% of the small bowel; not often performed because it takes several hours to perform, causes patient discomfort, and does not have any other capabilities aside from transmitting images. (Small intestine. Schwart's Principles of Surgery, 8th ed. In AccessSurgery. 1/15/2009)

1/12/09

Do patients who undergo recurrent CT scanning have increased risk of developing cancer?

Review article from New England Journal of Medicine

12/15/08

How useful is MRI for screening women at high risk for breast cancer?

prospective study and meta-analysis

12/12/08

Review of alpha-1 antitrypsin deficiency and hepatopulmonary syndrome

Review articles:
Gary Rachelefsky, D. Kyle Hogarth. Issues in the diagnosis of [alpha]1-antitrypsin deficiency, J Allergy Clin Immun. April 2008;121:833-838.

Kohnlein T, Welte T. Alpha-1 antitrypsin deficiency: pathogenesis, clinical presentation, diagnosis, and treatment. American J Med. 2008;121: 3-9.

Article on hepatic involvement in pulmonary diseases (AT deficiency, sarcoidosis):
Layden TJ, et al. Hepatic manifestations of pulmonary diseases. Clinics in Liver Disease. 2002;6:969-979.

Review on hepatopulmonary syndrome and related letter on platypnea:
Hepatopulmonary syndrome--a liver-induced lung vascular disorder. N Engl J Med. 2008 May 29;358:2378-87.
The hepatopulmonary syndrome. N Engl J Med. 2008 Aug 21;359:866-867.

12/11/08

What are the clinical features of Legionnaires' disease?

Review article on Legionella infection (includes discussion of sensitivity of urine antigen test)

Diederen BMW. Legionella spp. and Legionnaires' disease. J Infect Dis. 2008;56 (1):1-12

12/4/08

When did blood banks begin testing donated blood for hepatitis C?

Excerpt from Mandell, Douglas, and Bennett's: Principles and Practice of Infectious Diseases,6th ed., Chapter 112, states that donors were screened for risk of
blood-borne viral infections in the 1980s and blood was tested for
HCV-specific antibodies beginning in May 1990

See also Donahue JG, et al: The declining risk of post-transfusion hepatitis C virus infection. N Engl J Med 1992; 327:369-373.