Early detection of multi-drug resistance and common mutations in Mycobacterium tuberculosis isolates from Delhi using GenoType MTBDRplus assay

PURPOSE

There is scarcity of prevalence data of multi-drug-resistant tuberculosis (MDR-TB) data and common mutations responsible in North India. This study aimed to detect MDR-TB among MDR-TB suspects from Delhi and mutation patterns using GenoType MTBDRplus assay.

MATERIALS AND METHODS

All MDR suspects in five districts of New Delhi were referred to the laboratory from 1 st October 2011 to 31 st December 2012 as per criterion defined by Programmatic Management of Drug Resistant Tuberculosis (PMDT). GenoType MTBDRplus assay was performed on 2182 samples or cultures and mutations in the rpoB gene for rifampicin (RIF) and katG and inhA genes for isoniazid (INH) were analyzed.

RESULTS

A total of 366 (16.8%) MDR-TB cases were diagnosed. MDR rate was found to be 32%, 16.6% and 10.2% during criterion A, B and C respectively. The most common mutation detected for RIF was S531L (59.0%) and for INH was S315T1 (88.3%). Mutations S531L and S315T1 occurred significantly higher in MDR strains as compared to RIF mono-resistant and INH mono-resistant strains, respectively. Average laboratory turn-around time (TAT) for dispatch of result to districts for test conducted on samples was 4.4 days.

CONCLUSION

GenoType MTBDRplus is a useful assay for rapid detection of MDR-TB. The common mutations for RIF and INH were similar to those seen in other regions. However, mutations determining MDR strains and mono-resistant strains differed significantly for both RIF and INH.

Phylogenetic associations with drug-resistant Mycobacterium tuberculosis isolates in a paediatric population

SETTING

Department of Microbiology, National Institute of Tuberculosis and Respiratory Diseases, New Delhi, India.

OBJECTIVES

As paediatric tuberculosis (TB) is a surrogate marker for actively transmitted disease in a community, we investigated drug resistance patterns of 97 Mycobacterium tuberculosis complex strains isolated from children and explored their phylogenetic associations.

DESIGN

A total of 111 paediatric patients who attended the out-patient department during the study period 2009-2011 and whose sputum samples were sent to the Microbiology Department for liquid culture and drug susceptibility testing (DST) were included in this study. DST and spoligotyping were performed on cultures positive for M. tuberculosis complex.

RESULTS

DST against four first-line drugs showed that 31 of 97 (32%) strains were pan-susceptible, while 66/97 (68%) were resistant to at least one drug, including 55/97 (56.7%) that were resistant to at least isoniazid and rifampicin (i.e., multidrug-resistant). The majority of the isolates (n = 81/90, 90%) belonged to the principal genetic group 1 strains, the most predominant spoligotyping clusters being spoligotyping international type (SIT)1/Beijing (n = 28), SIT26/CAS1-Delhi (n = 27) and SIT53/T1 (n = 6).

CONCLUSION

The involvement of Beijing and CAS1-Delhi clades in paediatric TB patients suggests that these two lineages play a major role in ongoing active transmission.

Use of tomotherapy in treatment of synchronous bilateral breast cancer: dosimetric comparison study

OBJECTIVE

Synchronous malignancy in both breasts is a rare incidence. The present study aims at dosimetric comparison of conventional bitangential radiotherapy (RT) technique with conventional [field-in-field (FIF)] and rotational [Helical TomoTherapy(®) and TomoDirect™ (TD); Accuray Inc., Sunnyvale, CA] intensity-modulated RT for patients with synchronous bilateral breast cancer (SBBC).

METHODS

CT data sets of 10 patients with SBBC were selected for the present study. RT was planned for all patients on both sides to whole breast and/or chest wall using the above-mentioned techniques. Six females with breast conservation on at least one side also had a composite plan along with tumour bed (TB) boost using sequential electrons for bitangential and FIF techniques or sequential helical tomotherapy (HT) boost (for TD) or simultaneous integrated boost (SIB) for HT.

RESULTS

All techniques produced acceptable target coverage. The hotspot was significantly lower with FIF technique and HT but higher with TD. For the organs at risk doses, HT resulted in significant reduction of the higher dose volumes. Similarly, TD resulted in significant reduction of the mean dose to the heart and total lung by reducing the lower dose volumes. All techniques of delivering boost to the TB were comparable in terms of target coverage. HT-SIB markedly reduced mean doses to the total lung and heart by specifically lowering the higher dose volumes.

CONCLUSION

This study demonstrates the cardiac and pulmonary sparing ability of tomotherapy in the setting of SBBC.

ADVANCES IN KNOWLEDGE

This is the first study demonstrating feasibility of treatment of SBBC using tomotherapy.

Total replacement of a lung by tuberculosis pneumatocele--an unusual post-tuberculosis sequel

Total replacement of a lung by pneumatocele in pulmonary tuberculosis is rare. The formation of pneumatoceles in adult pulmonary tuberculosis can occur before, during or after anti-tuberculosis treatment. A case of pneumatocele formation in a 19-year young female following pulmonary tuberculosis is reported. The left lung was completely replaced by pneumatocele. Total replacement of a lung by pneumatocele inspite of successful chemotherapy of tuberculosis is rare and should be considered as one of the differential diagnosis for acquired cysts of the lung.

Combined avulsion fracture of the tibial tuberosity and lateral tibial plateau in an adolescent: case report

Avulsion of the tibial tuberosity is uncommon. It is usually an athletic injury, accounting for less than 3% of all epiphyseal injuries. We report the case of an avulsion fracture of the tibial tuberosity with unusual articular involvement of the lateral tibial plateau treated with open reduction and internal fixation using cancellous screws. The result was excellent, with complete union of the fracture site, full range of movement at three months and return to normal athletic activity within six months with no complications.

Trends in the annual risk of tuberculous infection in India

SETTING

Twenty-four districts in India.

OBJECTIVES

To evaluate trends in annual risk of tuberculous infection (ARTI) in each of four geographically defined zones in the country.

STUDY DESIGN

Two rounds of house-based tuberculin surveys were conducted 8-9 years apart among children aged 1-9 years in statistically selected clusters during 2000-2003 and 2009-2010 (Surveys I and II). Altogether, 184,992 children were tested with 1 tuberculin unit (TU) of purified protein derivative (PPD) RT23 with Tween 80 in Survey I and 69,496 children with 2TU dose of PPD in Survey II. The maximum transverse diameter of induration was measured about 72 h after test administration. ARTI was computed from the prevalence of infection estimated using the mirror-image method.

RESULTS

Estimated ARTI rates in different zones varied between 1.1% and 1.9% in Survey I and 0.6% and 1.2% in Survey II. The ARTI declined by respectively 6.1% and 11.7% per year in the north and west zones; no decline was observed in the south and east zones. National level estimates were respectively 1.5% and 1.0%, with a decline of 4.5% per year in the intervening period.

CONCLUSION

Although a decline in ARTI was observed in two of the four zones and at national level, the current ARTI of about 1% in three zones suggests that further intensification of TB control activities is required.

WHO guidelines for the programmatic management of drug-resistant tuberculosis: 2011 update

The production of guidelines for the management of drug-resistant tuberculosis (TB) fits the mandate of the World Health Organization (WHO) to support countries in the reinforcement of patient care. WHO commissioned external reviews to summarise evidence on priority questions regarding case-finding, treatment regimens for multidrug-resistant TB (MDR-TB), monitoring the response to MDR-TB treatment, and models of care. A multidisciplinary expert panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations. The recommendations support the wider use of rapid drug susceptibility testing for isoniazid and rifampicin or rifampicin alone using molecular techniques. Monitoring by sputum culture is important for early detection of failure during treatment. Regimens lasting ≥ 20 months and containing pyrazinamide, a fluoroquinolone, a second-line injectable drug, ethionamide (or prothionamide), and either cycloserine or p-aminosalicylic acid are recommended. The guidelines promote the early use of antiretroviral agents for TB patients with HIV on second-line drug regimens. Systems that primarily employ ambulatory models of care are recommended over others based mainly on hospitalisation. Scientific and medical associations should promote the recommendations among practitioners and public health decision makers involved in MDR-TB care. Controlled trials are needed to improve the quality of existing evidence, particularly on the optimal composition and duration of MDR-TB treatment regimens.

Electron arc therapy for bilateral chest wall irradiation: treatment planning and dosimetric study

AIMS

The treatment of patients with synchronous bilateral breast cancer is a challenge. We present a report of dosimetric data of patients with bilateral chest walls as the target treated with electron arc therapy.

MATERIALS AND METHODS

Ten consecutive patients who had undergone electron arc therapy to the bilateral chest wall for breast cancer were analysed. After positioning and immobilisation, patients underwent computed tomography scans from the neck to the upper abdomen. Electron arc plans were generated using the PLATO RTS (V1.8.2 Nucletron) treatment planning system. Electron energy was chosen depending upon the depth and thickness of the planning target volume (PTV). For all patients, the arc angle ranged between 80 and 280° (start angle 80°, stop angle 280°). The homogeneity index, coverage index and doses to organs at risk were evaluated. The patient-specific output factor and thermoluminescence dosimetry (TLD) measurements were carried out for all patients. The total planned dose to the PTV was 50Gy/25 fractions/5 weeks.

RESULTS

The mean PTV (± standard deviation) was 568.9 (±116)cm(3). The mean PTV coverage was 89 (±5.8)% of the prescribed dose. For the right lung, the mean values of D(1) and D(10) were 46 (±7.6) and 30 (±9)Gy, respectively. For the left lung, the mean values of D(1) and D(10) were 45 (±7) and 27 (±8)Gy, respectively. For the heart, the mean values of D(1), D(5) and D(10) were 21 (±15), 13.5 (±12) and 9 (±9)Gy, respectively. The mean values of TLD at various pre-specified locations on the chest wall surface were 1.84, 1.82, 1.82, 1.89 and 1.78Gy, respectively

CONCLUSION

The electron arc technique for treating the bilateral chest wall is a feasible and pragmatic technique. This technique has the twin advantages of adequate coverage of the target volume and sparing of adjacent normal structures. However, compared with other techniques, it needs a firm quality assurance protocol for dosimetry and treatment delivery.

Assessment of compliance to treatment and efficacy of a resource-sparing hypofractionated radiotherapy regimen in patients with poor-prognosis high-grade gliomas

INTRODUCTION

The optimal radiotherapeutic management of poor-prognosis (elderly and/or poor performance status) high-grade gliomas (HGG) remains controversial. Hypofractionated radiotherapy (hypoRT) has been shown to be non-inferior to daily conventionally fractionated radiotherapy. This study aimed to assess the compliance to treatment and efficacy of a resource-sparing hypoRT regimen in this subset.

MATERIALS AND METHODS

The resource-sparing hypoRT regimen was delivered once weekly (5Gy/fraction) for seven fractions to a total dose of 35Gy in seven fractions over six weeks. Compliance to planned treatment and factors that could potentially influence it were analyzed.

RESULTS

Between January 2004 and October 2009, 63 patients with poor-prognosis HGG (age range 40-78 years; Karnofsky performance score ≤70) were offered resource-sparing hypoRT regimen. Twenty eight of 63 patients completed planned course of treatment giving a treatment compliance rate of 44%. Six (9.5%) patients did not receive even a single fraction of radiation after simulation/planning. Thirty eight patients (60%) received ≥3 fractions and were on treatment for at least two weeks. Performance status (P = 0.05) and grade (P = 0.04) significantly impacted upon compliance. Median overall survival for the cohort of 28 patients who completed planned course of treatment was 7.4 months (95% confidence interval: 4.4-10.5 months).

CONCLUSIONS

The treatment compliance to a resource-sparing once-weekly hypoRT regimen in poor-prognosis HGG has been somewhat suboptimal and discouraging, possibly due to the protracted scheduling over six weeks. Over 60% of patients were on treatment for two weeks, suggesting that short-course schedules could more likely ensure compliance.

Radiation therapy with implanted cardiac pacemaker devices: a clinical and dosimetric analysis of patients and proposed precautions

AIMS

To report the radiation planning dosimetric aspects and clinical outcomes of patients with implanted cardiac pacemakers.

MATERIALS AND METHODS

Between 2005 and 2009, eight patients with in situ cardiac pacemakers of varied primary site were treated at our hospital. All patients underwent computed tomography-based treatment planning. The target volumes, organs at risk and pacemaker device were all contoured. A treatment plan optimally covering the target area and maximally sparing the pacemaker was generated. All patients were evaluated at baseline, during radiotherapy and after radiotherapy conclusion by a cardiologist as well as pacemaker company personnel.

RESULTS

The median age at presentation was 67 (range 53-77) years. There were three men with head and neck primaries, two men with lung primaries and three women with breast primaries. The prescribed dose ranged from 45 to 70 Gy in 25-35 fractions with a daily dose of 1.8-2.0 Gy. Four patients had the pacemaker implanted on the same side as the radiotherapy target. The dose ranges for the minimum, mean and maximum doses to the pacemaker were 0.06-2.0, 0.07-20.6 and 0.14-60.0 Gy, respectively. Radiation therapy was safely delivered in all patients without any untoward effects. At 5 months of median follow-up, all patients were well with no malfunction of the pacemaker.

CONCLUSION

A series of eight patients with in situ pacemakers treated with radiotherapy is reported. Radiotherapy can be safely delivered in patients with implanted cardiac pacemakers. However, it mandates a cautious approach in planning and treatment delivery to ensure the least possible dose to the pacemaker. Close liaison with the cardiologist and a pacemaker clinic before, during and after the course of treatment is essential to ensure patient safety.

Smear microscopy as surrogate for culture during follow up of pulmonary MDR-TB patients on DOTS Plus treatment

BACKGROUND

DOTS Plus site at LRS Institute, New Delhi, covering 1.8 million population.

AIMS

To ascertain if sputum smear could be used as a surrogate for culture during intensive phase of treatment of MDR-TB patients thereby enabling early shift from intensive phase to continuation phase, reducing the need for frequent cultures and saving time and cost in their management.

METHODS

The study is a retrospective analysis of 138 MDR-TB patients on DOTS Plus treatment whose sputum samples were simultaneously subjected to smear microscopy and culture, monthly during Intensive Phase and once in two months during Continuation Phase. Sputum results in the treatment card were supplemented from laboratory register, if required, and analyzed. Predictive values, sensitivity and specificity of smear were compared with culture results.

RESULTS

The Negative Predictive Value (NPV) of smear was high from the 3rd month onwards (above 91%), at four months 98% or more and approached 100% from eight months onwards. The specificity of smear test gradually increased during treatment and from five months onwards, it was above 90%.

CONCLUSIONS

Considerable correlation was observed between sputum smear and culture during follow up of DOTS Plus treatment in the Intensive Phase. Accordingly, sputum smears can be recommended instead of culture.

Quality of life after accelerated partial breast irradiation in early breast cancer: matched pair analysis with protracted whole breast radiotherapy

AIMS

To compare the quality of life of women with early breast cancer treated with either accelerated partial breast irradiation (APBI) or whole breast radiotherapy (WBRT).

MATERIALS AND METHODS

After matching for the American Brachytherapy Society criteria, the general European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and the breast cancer-specific BR23 modules were given to 48 women (23 APBI and 25 WBRT) who attended the radiotherapy clinic between May 2006 and December 2006 at Tata Memorial Hospital.

RESULTS

The median follow-up of patients in both groups was 3 years. The reliability and validity of the English and translated versions of the questionnaires were tested by Cronbach alpha (0.67-0.96) and Pearson's correlation for scale-scale correlation statistic (0.013-0.505). The scores for social functioning and financial difficulties in QLQ-C30 showed a trend towards a better outcome in the APBI group (P=0.025 and 0.019, respectively) and body image in BR23 was significantly better in the APBI group as compared with the WBRT group (P=0.005). When the analysis was restricted to women receiving chemotherapy in order to eliminate the confounding effect of the heterogeneous use of chemotherapy in the WBRT group, the difference in social functioning was not significant. However, financial difficulties and body image showed a trend towards a worse outcome in the WBRT group.

CONCLUSION

Favourable long-term results of APBI in terms of superior body image perception and lesser financial difficulties compared with WBRT need to be confirmed in larger prospective studies investigating the effect of APBI on quality of life and health economics in different ethnic groups and health care set-ups.

Seven-year DOTS-Plus pilot experience in India: results, constraints and issues

BACKGROUND

India is initiating the DOTS-Plus strategy at the national level.

OBJECTIVES

To highlight the results, constraints and issues of a pilot DOTS-Plus experience in an urban setting in India.

METHODS

Records of 126 patients with multidrug-resistant tuberculosis (MDR-TB) enrolled from January 2002 to December 2006, who received a daily fully supervised standardised treatment regimen under a pilot DOTS-Plus study in India, were analysed retrospectively.

RESULTS

Of the 126 patients enrolled, 61% were cured, 19% died, 18% defaulted and 3% failed treatment. There was an average delay of 5 months in the diagnosis of MDR-TB and a subsequent delay of approximately 3.3 months in initiating treatment. Of the 24 patients who died, 29% did so within a month of starting treatment. Migration was the most common reason for default. Cycloserine (CYC) had to be stopped in 15 patients and kanamycin (KM) in five due to major adverse effects.

CONCLUSIONS

The DOTS-Plus programme in resource-poor settings may provide reasonable results; however, it may confront significant operational difficulties in the timely diagnosis and early initiation of treatment. Early diagnosis and start of treatment may prevent some deaths. Default is commonly due to migration. CYC proved to be the most toxic drug, followed by KM.

High-precision radiotherapy for craniospinal irradiation: evaluation of three-dimensional conformal radiotherapy, intensity-modulated radiation therapy and helical TomoTherapy

This study aimed to establish the feasibility of intensity-modulated radiation therapy (IMRT) in craniospinal irradiation (CSI) using conventional linear accelerator (IMRT_LA) and compare it dosimetrically with helical TomoTherapy (IMRT_Tomo) and three-dimensional conformal radiotherapy (3DCRT). CT datasets of four previously treated patients with medulloblastoma were used to generate 3DCRT, IMRT_LA and IMRT_Tomo plans. A CSI dose of 35 Gy was prescribed to the planning target volume (PTV). IMRT_LA plans for tall patients were generated using an intensity feathering technique. All plans were compared dosimetrically using standardised parameters. The mean volume of each PTV receiving at least 95% of the prescribed dose (V(95%)) was >98% for all plans. All plans resulted in a comparable dose homogeneity index (DHI) for PTV_brain. For PTV_spine, IMRT_Tomo achieved the highest mean DHI of 0.96, compared with 0.91 for IMRT_LA and 0.84 for 3DCRT. The best dose conformity index was achieved by IMRT_Tomo for PTV_brain (0.96) and IMRT_LA for PTV_spine (0.83). The IMRT_Tomo plan was superior in terms of reduction of the maximum, mean and integral doses to almost all organs at risk (OARs). It also reduced the volume of each OAR irradiated to various dose levels, except for the lowest dose volume. The beam-on time was significantly longer in IMRT_Tomo. In conclusion, IMRT_Tomo for CSI is technically easier and potentially dosimetrically favourable compared with IMRT_LA and 3DCRT. IMRT for CSI can also be realised on a conventional linear accelerator even for spinal lengths exceeding maximum allowable field sizes. The longer beam-on time in IMRT_Tomo raises concerns about intrafraction motion and whole-body integral doses.

Five-year survival data in newly diagnosed glioblastoma treated with radiotherapy along with concurrent and adjuvant temozolomide

e13009

Background: We report 5-year survival data in patients with newly diagnosed glioblastoma treated with radiotherapy along with concurrent and adjuvant temozolomide (TMZ). Methods: Between March 2001 to April 2008, 81 patients with newly diagnosed histopathologically proven glioblastoma underwent surgery followed by external radiotherapy to a total dose of 60 Gy in 30 fractions over 6 weeks. Concurrent oral TMZ (75 mg/m2) was given daily with RT followed by adjuvant TMZ for 5 days every 28 days for six cycles (150 mg/m2 for the first cycle and 200 mg/m2 for rest of the cycles). Patients were monitored clinicoradiologically as per standard practice. Results: Patients aged between 11–73 years with a median age of 49 years (60 males, 21 females). Forty per cent of patients underwent a gross total resection of tumour, 44% had partial resection, and 16% an open or stereotactic biopsy only. 79% of the patients had a post-operative Karnofsky Performance Score (KPS) of >80. All six adjuvant cycles were completed in 68%. The 2-, 3-, 4-, and 5-year survival was 34%, 24%, 11%, and 11%, respectively (95% CI 14.03–21.96). The median overall and progression-free survival was 18 (2–92 months) and 16 months (2–72 months), respectively. On multivariate analysis, completion of all six cycles of adjuvant TMZ was associated with significantly better survival (p = 0.000). Neurological performance score (NPS) of 2–3 (p = 0.06) and Recursive Partitioning Analysis class V (p = 0.093) showed a trend towards poorer outcome. Treatment was generally well tolerated with only 2.5% of patients developing grade 3 anemia, leucopoenia, and neutropenia. Grade 3 or 4 thrombocytopenia was seen in 5% patients. Conclusions: Concurrent radiotherapy and TMZ followed by adjuvant TMZ results in encouraging survival even at a long follow-up.

No significant financial relationships to disclose.