Nosocomial exposure to tuberculosis – experience in an Internal Medicine ward and review of the recommendations for risk-control

Abstract

Context: Tuberculosis (Tb) is the 2nd death cause from infectious disease in the world. Portugal is a high incidence country. In the majority of Hospitals in Portugal, Tb patients are initialy admitted to Internal Medicine
wards. In the absence of isolation rooms with negative pressure, there are
recommendations for other attitudes that minimize the risk of nosocomial
transmission of Tb.
Objectives: To evaluate the risk-control attitudes that were taken
facing hospitalized Tb patients in an Internal Medicine ward of a general
Hospital; to quantify the time of permanence of potencially infectious patients in the ward.
Patients and Methods: Retrospective analysis of the hospitalized
patients with Tb at an Internal Medicine ward with 33 beds, during the
period of 3 years. Inclusion criteria: previous Tb diagnosis with less
than 4 weeks of treatment; diagnosis during the hospitalization, with
treatment decision; microbiological diagnosis after withdrawal from
the ward. Evaluated attitudes: “separation” (curtains, increasing bed
intervals); use of mask; high efficiency particle aspirator; transference to other institution.
Results: In a total of 2810 admissions, 39 cases of Tb were included
(1,4%), 25 of them with pulmonary forms of disease. Sixteen of these
were high risk transmitters, with positive direct or cultural microbiological identification in respiratory secretions. The hospitalizations of these
patients completed 303 days (162 until the diagnosis and 141 after the
diagnosis), most of them (169 days) without risk-control attitudes. Among
the 141 days after the diagnosis, only in 7 were risk-control attitudes
not taken. Risk-control attitudes were taken in 14 patients, all of them
with pulmonary Tb. The 2 remaining patients only had cultural diagnosis,
after withdrawal from the ward.
Discussion and conclusions: In 14 of the 16 infectious patients, the
recommended risk-control attitudes were taken, after the diagnosis.
Despite this acceptable accomplishement, there were 169 hospitalization
days with risk of transmission, wich we can relate to late suspicion and/
or diagnosis. It is necessary to reduce the treshold for suspicion and
risk-control attitudes. The authors present some proposals that might
reduce the nosocomial exposure to Mycobacterium tuberculosis.