Paradoxical worsening in tuberculosis during therapy in an HIV-infected patient

Clinical characteristics of IRIS syndrome in patients with HIV and tuberculosis

BACKGROUND

Some patients with HIV/tuberculosis (TB) coinfection who are on anti-TB treatment and highly active antiretroviral therapy (HAART) will develop an exacerbation of symptoms, signs or radiological manifestations of TB that are not due to relapse or recurrence of their TB. The aetiology of these immune reconstitution inflammatory syndrome (IRIS) reactions is unknown but it is presumed that they occur, at least in part, as a consequence of HAART-related reconstitution of immunity.

METHODS

Patients who were diagnosed with their first episode of definitive or presumed TB between January 2001 and July 2003 were identified from the Chelsea and Westminster TB/HIV database. The patients were classified into those who developed IRIS and those who did not using a set definition of the syndrome. Demographic, clinical and laboratory data relating to both HIV and TB were compared between the two groups.

RESULTS

A total of 55 cases of TB were identified, of which 45 cases were confirmed on culture or gene probe and 10 were presumed cases. Fourteen cases (25.5%) developed IRIS with a median (range) duration of 2.53 (0.53-14.97) months. The median baseline CD4 [interquartile range (IQR)] for the IRIS group was significantly lower at 80 (33-117) cells/mm3 (P = 0.05) than the non-IRIS group at 139 (77-284) cells/mm3. A significantly greater proportion of patients in the IRIS group [11/14 (78.60%), P = 0.011] had baseline CD4 < 100cells/mm3 compared with the non-IRIS group [16/41 (39.0%)]. There was no significant difference between the two groups when comparing the log10 baseline viral load (VL). Eight (57.0%) patients in the IRIS group had disseminated TB at baseline compared with seven (17.0%) in the non-IRIS group (P = 0.006). In those who had a detectable VL at baseline, the median fold change (IQR) in CD4 from baseline to 3 months was significantly higher in the IRIS group patients, 1.5 (0.6-5.6), compared with 0.7 (-0.2 to 1.0) for those in the non-IRIS group (P = 0.046).

CONCLUSIONS

Patients who develop IRIS are more likely to present with disseminated TB, have a CD4 count < 100 cells/mm3 and have a prompt rise in CD4 count in the initial 3 months of HAART.

Risk factors for development of paradoxical response during antituberculosis therapy in HIV-negative patients

The risk factors for development of paradoxical response were studied in a cohort of 104 patients with culture-documented Mycobacterium tuberculosis infection. Paradoxical deterioration occurred in 16 (15.4%) patients (case group) during antituberculosis therapy, involving lungs and pleura (n=4), spine and paraspinal tissue (n=5), intracranium (n=3), peritoneum (n=2), bone and joint (n=1), and lymph node (n=1). The median time from commencement of treatment to paradoxical deterioration was 56 days (range, 20-109 days). Compared with 53 patients without clinical deterioration after antituberculosis therapy (control group), patients with paradoxical response were more likely to have extrapulmonary involvement (62.5% vs. 17.0%; P<0.05) at initial diagnosis, to have lower baseline lymphocyte counts (672+/-315 cells/microl vs. 1,328+/-467 cells/microl; P<0.001), and to exhibit a greater surge in lymphocyte counts (627+/-465 cells/microl vs. 225+/-216 cells/microl; P<0.05) during paradoxical response. Further studies on lymphocyte subsets and cytokine levels would be useful in understanding the exact immunological mechanisms involved in immunorestitution.

Paradoxical worsening of tuberculosis in HIV-infected persons

OBJECTIVE

To determine the incidence of paradoxical worsening of tuberculosis (TB) in HIV-infected persons.

DESIGN

Observational cohort study.

SETTING

Public, urban TB clinic.

PATIENTS

HIV-infected persons treated for TB between January 1, 1996, and December 31, 1999, and followed through June 30, 2000.

INTERVENTION

Patients received standard anti-TB therapy. Antiretroviral therapy was provided by primary medical providers. Patients receiving antiretroviral therapy were given nucleoside reverse transcriptase inhibitors alone or highly active antiretroviral therapy (HAART; nucleoside reverse transcriptase inhibitors in combination with a protease inhibitor or a nonnucleoside reverse transcriptase inhibitor).

MAIN OUTCOME MEASURE

Paradoxical worsening of TB.

RESULTS

There were 82 TB cases in 76 patients. Paradoxical worsening was identified in 6 of 82 cases (7%; 95% confidence interval, 3 to 15%). Paradoxical worsening occurred in 3 of 28 cases (11%) in patients receiving HAART and in 3 of 44 cases (7%) in patients not receiving antiretroviral therapy (p = 0.67). Cases complicated by paradoxical worsening were more likely to have both pulmonary and extrapulmonary disease at initial diagnosis than cases without paradoxical worsening (83% vs 24%; p = 0.006). TB relapse occurred in 2 of 6 cases (33%) in patients with paradoxical worsening and in 4 of 76 cases (5%) in patients without paradoxical worsening (p = 0.06).

CONCLUSIONS

Paradoxical worsening of TB occurred less frequently than in previous reports and was not associated with HAART. Paradoxical worsening also appeared to be associated with an increased risk of TB relapse. Further studies are warranted to better characterize the risk factors for paradoxical worsening and the appropriate duration of anti-TB therapy in patients in whom it occurs.