Increased risk of latent tuberculous infection among persons with pre-diabetes and diabetes mellitus

SETTING

Although diabetes mellitus (DM) is an established risk factor for active tuberculosis (TB) disease, little is known about the association between pre-DM, DM, and latent tuberculous infection (LTBI).

OBJECTIVE

To estimate the association between DM and LTBI.

DESIGN

We conducted a cross-sectional study among recently arrived refugees seen at a health clinic in Atlanta, GA, USA, between 2013 and 2014. Patients were screened for DM using glycosylated-hemoglobin (HbA1c), and for LTBI using the QuantiFERON(®)-TB (QFT) test. HbA1c and QFT results, demographic information, and medical history were abstracted from patient charts.

RESULTS

Among 702 included patients, 681 (97.0%) had HbA1c and QFT results. Overall, 54 (7.8%) patients had DM and 235 (33.8%) had pre-DM. LTBI was prevalent in 31.3% of the refugees. LTBI prevalence was significantly higher (P < 0.01) among patients with DM (43.4%) and pre-DM (39.1%) than in those without DM (25.9%). Refugees with DM (adjusted OR [aOR] 2.3, 95%CI 1.2-4.5) and pre-DM (aOR 1.7, 95%CI 1.1-2.4) were more likely to have LTBI than those without DM.

CONCLUSION

Refugees with DM or pre-DM from high TB burden countries were more likely to have LTBI than those without DM. Dysglycemia may impair the immune defenses involved in preventing Mycobacterium tuberculosis infection.

Determining TB rates and TB case burden for refugees

SETTING

DeKalb County, Georgia.

OBJECTIVES

To calculate and compare tuberculosis (TB) rates in refugees to US-born, total foreign-born (refugee and other), and other foreign-born persons and to determine the contribution of refugees to the county TB case burden.

METHODS

The study included: (1) collection of county TB case numbers and population figures from 1995 through 1999; (2) estimation of the refugee population; (3) comparison of TB rates; and (4) calculation of the refugee TB case burden. Sensitivity analysis was performed on refugee population estimates.

RESULTS

From 1995 through 1999, estimating that refugees made up 10% of the foreign-born population, the average TB rate for refugees was 83.2 per 100,000, compared with 12.7 for US-born persons. From 1997 through 1999, refugees had a seven-fold greater risk of having TB than US-born persons and a two-fold greater risk than other foreign-born persons. Refugees represented respectively 7.6% and 19.3% of the county and foreign-born TB case burdens. For TB rates to be equal among all foreign-born persons, refugees would need to make up 15-25% of the foreign-born population.

CONCLUSION

Despite overseas screening, refugees have high TB rates, and contribute substantially to the county TB case burden. Enhanced surveillance and targeted programs to address TB in refugees should be a public health priority.

Intravesical suramin in the prevention of transitional cell carcinoma

OBJECTIVES

To examine the effects of intravesical suramin on N-methyl-N-nitrosurea (MNU)-induced bladder tumors in Fischer 344 rats.

METHODS

Multiple cohorts of female rats received four biweekly intravesical instillations of MNU. A control group received no other treatment, the experimental group received 25 mg/kg intravesical suramin twice a week beginning at week 6.

RESULTS

After 18 weeks from the first instillation of MNU, 60% to 65% of control animals developed papillary transitional cell carcinoma, compared with only 0% to 10% of the suramin-treated animals (P = 0.01 to P = 0.0007). There was no local or systemic toxicity observed.

CONCLUSIONS

Intravesical suramin is an effective chemopreventative therapy for transitional cell carcinoma in vivo with minimal toxicity.