Yuang-Shuang Liaw

Empirical treatment with a fluoroquinolone delays the treatment for tuberculosis and is associated with a poor prognosis in endemic areas

Background: A study was conducted to evaluate the effect of the empirical use of fluoroquinolones on the timing of antituberculous treatment and the outcome of patients with tuberculosis in an endemic area. Methods: All patients with culture confirmed tuberculosis aged ⩾14 years diagnosed between July 2002 and December 2003 were included and their medical records were reviewed. Results: Seventy nine (14.4%) of the 548 tuberculosis patients identified received a fluoroquinolone (FQ group), 218 received a non-fluoroquinolone antibiotic (AB group), and 251 received no antibiotics before antituberculous treatment. Fifty two (65.8%) experienced clinical improvement after fluoroquinolone use. In the FQ group the median interval from the initial visit to starting antituberculous treatment was longer than in the AB group and in those who received no antibiotics (41 v 16 v 7 days), and the prognosis was worse (hazard ratio 6.88 (95% CI 1.84 to 25.72)). More patients in the FQ and AB groups were aged >65 years (53.2% and 61.0% v 31.5%), had underlying disease (53.2% and 46.8% v 34.3%), and were hypoalbuminaemic (67.2% and 64.9% v 35.1%). Of the nine mycobacterial isolates obtained after fluoroquinolone use from nine patients whose initial isolates were susceptible to ofloxacin, one (11.1%) was resistant to ofloxacin (after fluoroquinolone use for 7 days). Independent factors for a poor prognosis included empirical fluoroquinolone use, age >65, underlying disease, hypoalbuminaemia, and lack of early antituberculous treatment. Conclusions: 14.4% of our patients with tuberculosis received a fluoroquinolone before the diagnosis. With a 34 day delay in antituberculous treatment and more frequent coexistence of underlying disease and hypoalbuminaemia, empirical fluoroquinolone treatment was associated with a poor outcome. Mycobacterium tuberculosis isolates could obtain ofloxacin resistance within 1 week.

Sonographic septation: a useful prognostic indicator of acute thoracic empyema.

The aim of this study was to identify sonographic predictors of patient outcomes or need for surgical intervention of acute thoracic empyema. All patients with a clinical diagnosis of thoracic empyema underwent transthoracic ultrasonographic examination and thoracentesis at admission. According to the presence or absence of septa in sonographic images, the patients were classified into two groups: septated and nonseptated. Sonographic findings were analyzed with respect to duration of hospital stay, chest tube drainage, and treatment efficacy. A total of 163 consecutive patients were included in the study (83 patients with septated and 80 with nonseptated sonographic images). The mean duration of hospital stay (35.4 versus 27.0 days, P = 0.009) and chest tube drainage (13.1 versus 7.6 days, P < 0.001) for the patients with septa were significantly longer than for those without septa. The patients with septa were more likely to undergo intrapleural fibrinolytic therapy (63.8% versus 38.8%, odds ratio 2.79, P = 0.001) and surgical intervention (24.3% versus 7.5%, odds ratio 3.92, P = 0.004). We concluded that sonographic septation is a useful sign to predict the need for subsequent intrapleural fibrinolytic therapy and surgical intervention in cases of acute thoracic empyema. Early fibrinolytic therapy or even surgical intervention may be indicated in patients with sonographic septations.

Prediction of the Tuberculosis Reinfection Proportion from the Local Incidence

BACKGROUND Reinfection is a major contributor to tuberculosis (TB). It seems that the higher the local incidence, the higher the proportion of reinfection. METHODS Based on a systematic review of the literature, we established a regression model to predict the reinfection proportion from the local incidence. We then used our local data to verify the algorithm. RESULTS Of the 23 studies addressing reinfection in recurrent TB, 6 were population based. The reinfection proportion was correlated with the local incidence (reinfection proportion=-29.7+36.8 x log Incidence) (95% confidence interval [CI] for coefficient, 15.3-58.3; R2=0.849). The reinfection proportion in Taiwan (incidence, 62.4/100,000 people) was estimated to be 36% (95% CI, 3%-69%). Of our 49 recurrent patients, 51% had reinfection. Patients with reactivation seemed more likely to have underlying diseases and less likely to be smear positive. The relapse isolates seemed more resistant than the initial isolates. CONCLUSIONS The regression model could possibly predict the TB reinfection proportion from the local incidence. This algorithm is probably helpful in policy making for TB control programs. In areas where TB is endemic, reinfection might be responsible for >50% of TB cases, and aggressive surveillance to detect asymptomatic carriers could be an important strategy for controlling the disease.

Clinical spectrum of tuberculosis in older patients

Clinical Spectrum of Tuberculosis in Older Patients

Drug Resistance Pattern of Mycobacterium tuberculosis in a University Hospital in Taiwan, 1998-2002

BACKGROUND AND PURPOSE During 1998-2002, most specialized tuberculosis (TB) hospitals in Taiwan were closed; as a result, more TB patients are being managed in general hospital settings. This study investigated the prevalence, patterns and risk factors of drug-resistant Mycobacterium tuberculosis at a university hospital in the 5 years after decentralization of the TB administrative and clinical control infrastructure which occurred during the implementation of the national health insurance system in Taiwan. METHODS A total of 1411 initial isolates of M. tuberculosis from specimens collected during January 1998 through December 2002 were tested for drug susceptibility of first-line anti-TB drugs using the agar proportional method. RESULTS The numbers of newly diagnosed culture-positive TB patients increased from 139 in 1998 to 380 in 2002. The drug resistance pattern of M. tuberculosis among these isolates was as follows: 268 (19.0%) strains were resistant to isoniazid, 86 (6.1%) to rifampin, 221 (15.7%) to ethambutol, 141 (10.0%) to streptomycin, and 430 (30.5%) to 1 of these 4 drugs. Multidrug resistance (MDR), i.e., resistance to at least rifampin and isoniazid, was observed in 72 isolates (5.1%). Of the 1411 patients, isolates from patients with age < 65 years had a higher multiple drug resistance rate than those from patients with age > or = 65 years (57/781, 7.3% vs 15/630, 2.4%; p < 0.001). In the analysis of risk factors for MDR, patients with MDR isolates had a significantly higher incidence of previous TB history, anti-TB therapy, longer duration of symptoms, cavitary lesions in chest X-ray, and mortality. CONCLUSION A dramatic increase in cases of TB among patients treated at this university hospital was seen after the decentralization of the TB control infrastructure in Taiwan. The prevalence of drug resistance in isolates from culture-positive TB patients was 30.5% and the prevalence of MDR was 5.1%.

Mycobacterium tuberculosis inducing disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) can develop infrequently in patients with tuberculosis and has a very high mortality rate. We conducted a retrospective study to evaluate the incidence of tuberculosis-induced DIC and to investigate the clinical manifestation, outcome, and prognostic factors of such patients. From January 2002 to December 2003, all culture-proven tuberculosis patients who developed DIC before starting anti-tuberculosis treatments were selected for this study. Patients who had other clinical conditions or were infected by other pathogens that may have been responsible for their DIC were excluded. Survival analysis was performed for each variable with possible prognostic significance. Our results showed that 27 (3.2%) out of the 833 patients with culture-proven tuberculosis had tuberculosis-induced DIC with a mortality rate of 63.0%. The most common clinical manifestations were fever (63.0%) and multiple patches of pulmonary consolidation (59.3%). Seven (25.9%) patients had disseminated tuberculosis. Twelve (44.4%) developed acute respiratory distress syndrome and three (11.1%) were associated with hemophagocytosis. Twenty-four (88.9%) patients had findings that were unusual for an acute bacterial infection, such as positive acid-fast smear, miliary pulmonary lesions, lymphocytotic exudative pleural effusion, and mediastinal lymphadenopathy. Early anti-tuberculosis treatment significantly improved survival. In conclusion, tuberculosis can cause DIC. Patients with non-miliary, non-disseminated tuberculosis could also develop the rare clinical manifestation. Since the prognosis was very poor in patients not treated at an early stage, a high index of suspicion is required, especially in those with clinical findings suggestive of tuberculosis.

Diagnosis of pulmonary arteriovenous malformations by colour Doppler ultrasound and amplitude ultrasound angiography

BACKGROUND The clinical value of colour Doppler ultrasound and amplitude ultrasound angiography in the diagnosis and follow up of pulmonary arteriovenous malformations (PAVM) was investigated. METHODS Six consecutive patients suspected by clinical appearance and abnormal chest radiographic findings of having PAVM were included in the study. Ultrasonography was performed first by real time grey scale imaging then by colour Doppler imaging and amplitude ultrasound angiography in a random order. All were later proved by angiography to have PAVM. RESULTS The ultrasound study was successfully performed in all six patients. A total of eight lesions was detected. The real time grey scale image of PAVM revealed well defined hypoechoic subpleural nodules with strong posterior acoustic enhancement. Colour Doppler ultrasound of PAVM showed turbulent flow, manifest as an area of intense colour with high and mixed velocities (reticulated or mosaic-like pattern). Anatomical continuity was demonstrated in some PAVM. Amplitude ultrasound angiography can delineate a tangled vascular structure with a clear vessel wall and anatomical continuity as well as conventional angiography. Spectral wave analysis showed a relatively low impedance flow presenting with high peak systolic velocity (mean 44.4 cm/s) and relatively high diastolic velocity (mean 19.3 cm/s). The mean pulsatility index (PI) and resistive index (RI) were 1.80 and 0.49, respectively. In two patients who received embolotherapy the colour Doppler ultrasound scan obtained after the procedure showed that the previous focal areas of colour flow signals disappeared or diminished in size. This was compatible with the decrease in, or absence of, blood flow demonstrated by angiography after embolotherapy. CONCLUSIONS Combined colour Doppler ultrasound and amplitude ultrasound angiography are useful non-invasive techniques for diagnosing PAVM and provide an alternative approach to angiography in evaluating the efficacy of embolotherapy.

Clinical Features and Predictors of a Complicated Treatment Course in Peripheral Tuberculous Lymphadenitis

BACKGROUND/PURPOSE There remains uncertainty regarding the treatment strategy for patients with peripheral tuberculous lymphadenitis (pTBL) in areas endemic for tuberculosis. The purpose of this study was to demonstrate the clinical features and assess the predictors of a complicated treatment course in pTBL. METHODS A retrospective analysis of 97 pTBL patients from January 1995 through to December 2004 was conducted. Patient characteristics with and without a complicated treatment course, defined as prolonged treatment (>9 months) and/or relapse, were compared for determining the predictors. RESULTS The disease occurred predominantly in females (57.7%) with a mean age of 37. Most patients (72%) were asymptomatic. Cervical nodes were the most common (72%) manifestations. Fifty-six patients completed a 6-9 month course of therapy without relapse; 28 had a prolonged but complete treatment course, and 13 relapsed within a mean of 8.5 months after treatment (range, 3-42 months; median, 7.8 months). Of 97 pTBL patients, six had enlarged or newly appeared lymph nodes during treatment. Multivariate analysis indicated that low body mass index and bilateral cervical nodes were independent determinants of a complicated treatment course with the odds ratios of 1.2 (95% CI, 1.01-1.41; p=0.042) and 3.9 (95% CI, 1.08-14.0; p=0.038), respectively. CONCLUSION This study found that pTBL is more likely to occur in young female patients. For patients who present with bilateral cervical nodes and low body mass index, a prolonged treatment course to ensure disease control should be considered.

Primary pulmonary botryomycosis with multiple adjacent organ involvement mimicking mucosa-associated lymphoid tissue lymphoma.

Botryomycosis is an unusual chronic suppurative disease characterized by the histological finding of sulphur granules containing the causative bacteria in an abscess. We describe a previously healthy 14-year-old girl who presented with chronic productive cough. Chest computed tomography (CT) revealed a right lower mass with involvement of the parietal pleura, chest wall, diaphragm, liver and costovertebral junction. Thoracostomy biopsy was performed due to suspicion of low-grade mucosa-associated lymphoid tissue lymphoma. However, histological analysis revealed a pulmonary botryomycosis. The right lower lung mass completely resolved after 3 months of antibiotics treatment. This case emphasizes that primary pulmonary botryomycosis with extensive contiguous involvement may not be distinguishable from lung cancer, lymphoma or fungal infection on chest CT.

Characterization of a 411-bp fragment of the rpoB gene in clinical isolates of Mycobacterium tuberculosis in a university hospital in northern Taiwan.

BACKGROUND AND PURPOSE This study analyzed rpoB gene mutation and its correlation with demographic and clinical data, and the drug resistance profile in 41 consecutive patients with rifampin (RIF)-resistant Mycobacterium tuberculosis isolated at National Taiwan University Hospital from 2000 to 2002. METHODS The 411-bp fragment of the rpoB gene from 94 M. tuberculosis isolates (including 41 RIF-resistant and 53 RIF-susceptible isolates) was amplified and sequenced. RESULTS Of the 41 RIF-resistant isolates, 87.8% (36/41) showed mutations in rpoB. The following mutations were identified: Ser531 (68.3%), His526 (9.8%), Ser522 (4.9%) and Gln513 (4.9%). No silent substitutions were observed. No mutation within the entire 411-bp fragment was found in 12.2% (5/41) of the RIF-resistant isolates and 100% (53/53) of the RIF-susceptible isolates. Patients whose RIF-resistant isolates did not have rpoB mutation had higher frequencies of the following characteristics: elderly, no previous history of tuberculosis, human immunodeficiency virus-negative, no extrapulmonary tuberculosis involvement and favorable prognosis. Drug resistance patterns in RIF-resistant M. tuberculosis strains were significantly correlated with isoniazid resistance, i.e., multidrug-resistant strains (90.2%). CONCLUSIONS RIF-resistant M. tuberculosis isolates with rpoB mutation were clustered in the 69-bp core region in this study. Rapid detection of RIF resistance could be achieved by testing for rpoB mutation in Taiwan.