Is Your Shower Like the Shower in the Bates Motel? Researchers analyzed the microbial population living inside showerheads. Ever since Alfred Hitchcock’s Psycho, showers have seemed potentially lethal. Janet Leigh, who played the victim in the famous murder scene at the Bates Motel, avoided them as much as possible thereafter. In a recent study, researchers investigated whether microbes in shower water might be as dangerous as a lurking Anthony Perkins. They analyzed ribosomal RNA sequences from the interior surfaces of 45 showerheads in nine American cities, sampling some on several occasions. The number of organisms identified at each site varied between 2 and 29, and the flora tended to be stable over time. The bacteria were mostly ubiquitous soil and water microbes that tend to form biofilms but rarely cause human infection.Mycobacterium avium and M. gordonae, however, were commonly found isolates, identified at much higher levels in the showerheads than in the feeding water. M. avium, especially, can cause disease when people with deficient cell-mediated immunity inhale it into the lungs, and some scientists have speculated that M. avium infections have increased as showers replace baths as the more popular bathing method. A reassuring finding was the rarity of Legionella pneumophila, because showers have occasionally been implicated as a source of Legionnaires disease.http://www.pnas.org/content/106/38/16393.full?linkType=FULL&journalCode=pnas&resid=106/38/16393

New Testing Combination May Reveal Latent Syphilis Reversing the usual order of syphilis tests produces additional positive results that may require treatment for late latent syphilis, according to a CDC study in MMWR. Recently, some labs have begun screening first with a treponemal test and then retesting reactive specimens with a nontreponemal test for confirmation, reversing the usual order. Reviewing results from four New York City labs, the CDC found that 3% of 117,000 samples were positive on the treponemal test but not on the nontreponemal test, so they would not have been identified using the traditional testing order. In such cases, a second treponemal test should be done if the patient has no history of syphilis treatment. If that test is also positive, “clinicians should discuss the possibility of infection and offer treatment to patients who have not been previously treated,” the CDC says. MMWR article (Free)

Unexplained False Positives Seen in Oral Rapid HIV Tests Two clusters of unexplained false-positive results from rapid oral HIV tests have occurred at New York City STD clinics, reports MMWR. The episodes, involving the OraQuick Advance Rapid HIV-1/2 Antibody Test, started in late 2005 and late 2007. After the first occurrence, clinics began following up reactive oral tests with immediate finger-stick whole-blood tests to reduce the number of false-positives. In the more recent cluster, the number of false-positive oral fluid tests increased from 0.51% in November 2007 to 1.11% of those tested in February of this year. The CDC still encourages rapid HIV testing because it increases the number of people who get tested and receive their results. Patients should be told the rapid test results are preliminary and require confirmation, the agency says. MMWR article (Free)

Screen Hypertensive Patients for Diabetes, USPSTF Advises 
Patients with blood pressure above 135/80 mm Hg should undergo screening for type 2 diabetes, the U.S. Preventive Services Task Force recommends in the current Annals of Internal Medicine. The group says that sustained pressure above 135/80 — whether the patient is under treatment for hypertension or not — should trigger screening. There is adequate evidence, the group reports, that lowering pressure below conventional target values in patients with diabetes will lower cardiovascular risks. There is not enough evidence available to weigh the benefits of screening for diabetes in asymptomatic adults with lower blood pressure. However, according to the task force, screening normotensives on an individual basis may be useful if it “would help inform decisions about coronary heart disease prevention strategies.” The task force made its recommendations after reviewing evidence published since 2003, the date of its previous statement. In addition, the group withdrew a recommendation to screen patients with hyperlipidemia for diabetes. Annals of Internal Medicine guidelines 
Annals of Internal Medicine review of evidence


Galectin-3-expression analysis in the surgical selection of follicular thyroid nodules with indeterminate fine-needle aspiration cytology: a prospective multicentre study ( Lancet Oncology DOI:10.1016/S1470-2045(08)70132-3 )


Background In the USA, about 30 200 well-differentiated thyroid carcinomas were diagnosed in 2007, but the prevalence of thyroid nodules is much higher (about 5% of the adult population). Unfortunately, the preoperative characterisation of follicular thyroid nodules is still a challenge, and many benign lesions, which remain indeterminate after fine-needle aspiration (FNA) cytology are referred to surgery. About 85% of these thyroid nodules are classified as benign at final histology. We aimed to assess the diagnostic effect of galectin-3 expression analysis in distinguishing preoperatively benign from malignant follicular thyroid nodules when FNA findings were indeterminate.
Methods 544 patients were enrolled between June 1, 2003, and Aug 30, 2006. We used a purified monoclonal antibody to galectin-3, a biotin-free immunocytohistochemical assay, and a morphological and phenotypic analysis of FNA-derived cell-block preparations. Galectin-3-expression analysis was applied preoperatively on 465 follicular thyroid proliferations that were candidates for surgery, and its diagnostic accuracy was compared with the final histology.
Findings 31 patients were excluded because they had small galectin-3-negative thyroid nodules; we did not have data for 47 patients; and one patient with an oncocytic nodule was excluded. 331 (71%) of the assessable 465 preoperative thyroid FNA samples did not express galectin-3. 280 (85%) of these galectin-3-negative lesions were classified as benign at final histology. Galectin-3 expression was detected, instead, in 134 of 465 (29%) thyroid proliferations, 101 (75%) of which were confirmed as malignant. The overall sensitivity of the galectin-3 test was 78% (95% CI 74–82) and specificity was 93% (90–95). Estimated positive predictive value was 82% (79–86) and negative predictive value was 91% (88–93). 381 (88%) of 432 patients with follicular thyroid nodules who were referred for thyroidectomy were correctly classified preoperatively by use of the galectin-3 test. However, 29 (22%) of 130 cancers were missed by the galectin-3 method.
Interpretation Our findings show that if the option of surgery was based theoretically on galectin-3 expression alone, only 134 thyroid operations would have been done in 465 patients; therefore a large proportion (71%) of unnecessary thyroid surgical procedures could be avoided, although a number of galectin-3-negative cancers could be potentially missed. The galectin-3 test proposed here does not replace conventional FNA cytology, but represents a complementary diagnostic method for those follicular nodules that remain indeterminate.

Don’t use urine microscopy to confirm microscopic haematuria( Published 29 June 2009, doi:10.1136/bmj.b2629 )
The presence of urinary myoglobin will generate occasional false positive results when using dipstick urine analysis for diagnosing microscopic haematuria. However, it is poor practice to attempt to confirm the presence of red cells by urine microscopy. Urinary red cells are lysed in acidic urine or after prolonged storage, and laboratory error is common in urine microscopy; the result of adopting such a policy is to convert a small false positive rate into a large false negative rate. If investigation or follow-up is contemplated, it is far better to omit this step and follow the advice of the UK Renal Association and the guideline from the National Institute for Health and Clinical Excellence (NICE). Whether it is valuable to investigate a patient under 40 presenting with microscopic haematuria who does not have hypertension, alert symptoms, proteinuria, or abnormal renal function is debatable. The fact that such patients are inappropriately (and often invasively) investigated ignores the high frequency of the condition, the very low pick up rate of significant disease, the possible complications, and the opportunity cost of such resource allocation. Many nephrologists now routinely return such referrals to primary care.


Cervical Cancer Risk Among Women Who Have Been Treated for CIN( J Natl Cancer Inst. 2009 May 20;101(10):696-7 )

Long-term risk for invasive cancer remained higher among women treated for CIN, especially those who underwent cryotherapy. For women who have been treated for cervical intraepithelial neoplasia (CIN), consensus about optimal surveillance strategies has not been reached. In a population-based cohort study, Canadian researchers compared cytologic and cancer-registry data from more than 37,000 women who had been treated for CIN 1, 2, or 3 with data from nearly twice as many women who had no CIN histories. Overall cumulative rates of CIN 2 or CIN 3 during the first 6 years after treatment were 14.0% for women who were originally treated for CIN 3 and 9.3% and 5.6% for those who had been treated for CIN 2 and CIN 1, respectively. Thirty-seven invasive cancers developed in the CIN cohort and six cancers occurred in the comparison cohort. After 6 years, annual rates of CIN 2 or CIN 3 in treated women under surveillance dropped to <1%, comparable to incidence in the general cohort. In the CIN cohort, risk for developing invasive cancer was higher in women who were aged ≥40 (adjusted odds ratio, 1.8), who initially had CIN 3 versus 1 or 2 (AOR, 4.1), or who had been treated with cryotherapy versus other therapies (AOR, 3.0). Comment: Good data on long-term outcomes after treatment for CIN have been lacking, and, despite several limitations, this study helps fill that void. Only women under active surveillance were evaluated. Moreover, women who underwent incomplete excisional procedures that did not yield clear surgical margins were excluded, which might have led to underestimates of recurrence risk following electrosurgical excision or cone biopsies. Overall, decisions about best therapy are difficult and must take into account cost and complication rates (both of which are usually lower for cryotherapy). Despite its weaknesses, this large study should help guide experts to develop evidence-based guidelines. I have heard clinicians tell patients with CIN 3 that as long as they have appropriate follow-up, they will not develop cancer. These results substantiate that women who have been treated for CIN are at long-term risk for subsequent cervical cancer.


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