Biomarkers of Tuberculosis Severity and Treatment Effect: A Directed Screen of 70 Host Markers in a Randomized Clinical Trial

More efficacious treatment regimens are needed for tuberculosis, however, drug development is impeded by a lack of reliable biomarkers of disease severity and of treatment effect. We conducted a directed screen of host biomarkers in participants enrolled in a tuberculosis clinical trial to address this need. Serum samples from 319 protocol-correct, culture-confirmed pulmonary tuberculosis patients treated under direct observation as part of an international, phase 2 trial were screened for 70 markers of infection, inflammation, and metabolism. Biomarker assays were specifically developed for this study and quantified using a novel, multiplexed electrochemiluminescence assay. We evaluated the association of biomarkers with baseline characteristics, as well as with detailed microbiologic data, using Bonferroni-adjusted, linear regression models. Across numerous analyses, seven proteins, SAA1, PCT, IL-1β, IL-6, CRP, PTX-3 and MMP-8, showed recurring strong associations with markers of baseline disease severity, smear grade and cavitation; were strongly modulated by tuberculosis treatment; and had responses that were greater for patients who culture-converted at 8weeks. With treatment, all proteins decreased, except for osteocalcin, MCP-1 and MCP-4, which significantly increased. Several previously reported putative tuberculosis-associated biomarkers (HOMX1, neopterin, and cathelicidin) were not significantly associated with treatment response. In conclusion, across a geographically diverse and large population of tuberculosis patients enrolled in a clinical trial, several previously reported putative biomarkers were not significantly associated with treatment response, however, seven proteins had recurring strong associations with baseline radiographic and microbiologic measures of disease severity, as well as with early treatment response, deserving additional study.

Role of Crystal Structure and Chalcogenide Redox Properties on the Oxidative Assembly of Cadmium Chalcogenide Nanocrystals

Oxidative assembly of metal chalcogenide nanocrystals (NCs) enables the formation of 2-D (dense) and 3-D porous structures without the presence of intervening ligands between particles that can moderate transport properties. This route has been demonstrated to be successful for a range of single-component structures including CdQ, PbQ, and ZnQ (Q = S, Se, Te). En route to the controllable assembly of multicomponent nanostructures, the roles of Q redox properties (2Q^2- → Q₂^2- + 2e) responsible for particle cross-linking and the native structure (cubic zinc blende vs hexagonal wurtzite) in the kinetics of assembly in single-component CdQ NCs are evaluated using time-resolved dynamic light scattering (TR-DLS). For wurtzite CdQ, the rates follow the ease of oxidation, with telluride as the fastest, followed by selenide and sulfide. However, when comparing CdS wurtzite (w) and zinc blende (zb), the cubic NCs exhibit surprisingly slow kinetics. NMR studies reveal the zb structure to have lower ligand coverage (by a factor of 4) relative to that of w, and the formation of free disulfide (the product of ligand oxidation) is slow. This is attributed to differences in the surface energies of w and zb facets, with w having polar (0001) facets of high energy compared to the neutral facets of the zb structure. The zb-CdS NCs prepared by low-temperature synthesis methods are likely to suffer from surface defects that may moderate reactivity. EPR studies suggest that zb-CdS has paramagnetic sulfur vacancies not present in w-CdS. These data suggest that structure plays an unexpectedly large role in the kinetics of CdQ NC oxidative assembly, providing a useful lever to moderate activities in multicomponent assemblies.

Bioavailability and tolerability of nebulised dexamethasone sodium phosphate in adult horses

BACKGROUND

Nebulisation of the injectable dexamethasone sodium phosphate (DSP) would offer an inexpensive way of delivering a potent corticosteroid directly to the lungs of horses with asthma. However, this approach would be advantageous only if systemic absorption is minimal and if the preservatives present in the formulation do not induce airway inflammation.

OBJECTIVE

To investigate the bioavailability of nebulised DSP and determine whether it induces airway inflammation or hypothalamic-pituitary-adrenal (HPA) axis suppression in healthy adult horses.

STUDY DESIGN

Randomised crossover experiment.

METHODS

Dexamethasone sodium phosphate was administered to six healthy adult horses at a dose of 5 mg q. 24 h for 5 days via nebulised, or intravenous (i.v.) routes. Plasma dexamethasone concentrations were measured by UPLC/MS-MS to calculate bioavailability. Cytological examination of bronchoalveolar fluid was performed at baseline and after the last dose of DSP. A validated chemiluminescent immunoassay was used to measure basal serum cortisol concentrations.

RESULTS

After nebulisation to adult horses, dexamethasone had a mean (±s.d.) maximum plasma concentration of 0.774 ± 0.215 ng/mL and systemic bioavailability of 4.3 ± 1.2%. Regardless of route of administration, there was a significant decrease in the percentage of neutrophils in bronchoalveolar lavage fluid over time. During i.v. administration, basal serum cortisol concentration decreased significantly from baseline to Day 3 and remained low on Day 5. In contrast, basal serum cortisol concentration did not change significantly during administration via nebulisation.

MAIN LIMITATIONS

Small sample size and short period of drug administration.

CONCLUSIONS

Dexamethasone sodium phosphate administered via nebulisation had minimal systemic bioavailability and did not induce lower airway inflammation or HPA axis suppression in healthy horses.

C septicum Complicating Hemolytic Uremic Syndrome: Survival Without Surgical Intervention

Clostridium septicum is an anaerobic bacterium that causes rapidly progressive myonecrosis, bacteremia, and central nervous system infection. It has been reported as a complication of Escherichia coli hemolytic uremic syndrome (HUS) in 8 children worldwide; 5 children died, and the 3 reported survivors had surgically treated disease. We present 3 cases of C septicum complicating HUS in children, including the first 2 reported cases of survival without surgical intervention. All patients presented with classic cases of HUS with initial clinical improvement followed by deterioration. Patient 1 had rising fever, tachycardia, and severe abdominal pain 24 hours after admission. She developed large multifocal intraparenchymal cerebral hemorrhages and died 12 hours later. Autopsy revealed C septicum intestinal necrosis, myonecrosis, and encephalitis. Patient 2 had new fever, increasing leukocytosis, and severe abdominal pain on hospital day 4. She was diagnosed with C septicum bacteremia and treated with metronidazole, meropenem, and clindamycin. Patient 3 had new fever and increasing leukocytosis on hospital day 3; blood cultures grew C septicum, and she was treated with penicillin. Patients 2 and 3 improved rapidly and did not require surgery. C septicum is a potential co-infection with E coli It thrives in the anaerobic environment of E coli-damaged intestinal mucosa and translocates to cause systemic infection. Fever, tachycardia, a rising white blood cell count, and abdominal pain out of proportion to examination are key findings for which physicians should be vigilant. Timely evaluation by anaerobic blood culture and early initiation of antibiotics are necessary to prevent fatalities.

Re-inventing adherence: toward a patient-centered model of care for drug-resistant tuberculosis and HIV

BACKGROUND

Despite renewed focus on molecular tuberculosis (TB) diagnostics and new antimycobacterial agents, treatment outcomes for patients co-infected with drug-resistant TB and human immunodeficiency virus (HIV) remain dismal, in part due to lack of focus on medication adherence as part of a patient-centered continuum of care.

OBJECTIVE

To review current barriers to drug-resistant TB-HIV treatment and propose an alternative model to conventional approaches to treatment support.

DISCUSSION

Current national TB control programs rely heavily on directly observed therapy (DOT) as the centerpiece of treatment delivery and adherence support. Medication adherence and care for drug-resistant TB-HIV could be improved by fully implementing team-based patient-centered care, empowering patients through counseling and support, maintaining a rights-based approach while acknowledging the responsibility of health care systems in providing comprehensive care, and prioritizing critical research gaps.

CONCLUSION

It is time to re-invent our understanding of adherence in drug-resistant TB and HIV by focusing attention on the complex clinical, behavioral, social, and structural needs of affected patients and communities.

Pathways and costs of care for patients with tuberculosis symptoms in rural Uganda

SETTING

Six district-level government health centers in rural Uganda and the surrounding communities.

OBJECTIVE

To determine pathways to care and associated costs for patients with chronic cough referred for tuberculosis (TB) evaluation in Uganda.

DESIGN

We conducted a cross-sectional study, surveying 64 patients presenting with chronic cough and undergoing first-time sputum evaluation at government clinics. We also surveyed a random sample of 114 individuals with chronic cough in surrounding communities. We collected information on previous health visits for the cough as well as costs associated with the current visit.

RESULTS

Eighty per cent of clinic patients had previously sought care for their cough, with a median of three previous visits (range 0-32, interquartile range [IQR] 2-5). Most (n = 203, 88%) visits were to a health facility that did not provide TB microscopy services, and the majority occurred in the private sector. The cost of seeking care for the current visit alone represented 28.8% (IQR 9.1-109.5) of the patients' median monthly household income.

CONCLUSION

Most patients seek health care for chronic cough, but do so first in the private sector. Engagement of the private sector and streamlining TB diagnostic evaluation are critical for improving case detection and meeting global TB elimination targets.

Special AT-rich sequence-binding protein 2 (SATB2) expression is sensitive but may not be specific for osteosarcoma as compared with other high-grade primary bone sarcomas

AIMS

The diagnosis of osteosarcoma, although important for eligibility in clinical trials and proper therapy, may be challenging when no bone or osteoid matrix is identified on biopsy. Therefore, other adjunct tests have been sought to help confirm the diagnosis. Special AT-rich sequence-binding protein 2 (SATB2) has been shown as a reliable marker of osteoblastic differentiation. The aim of this study was to examine SATB2 expression in osteosarcomas and other primary bone sarcomas, in order to evaluate its diagnostic utility in discriminating osteogenic from non-osteogenic sarcomas.

METHODS AND RESULTS

Forty-eight pretreated osteosarcoma biopsies, including 26 whole-section cases and 22 tumours on tissue microarrays, and 36 non-osteogenic bone sarcomas were evaluated. Forty-five of 48 (94%) osteosarcomas showed nuclear immunoreactivity for SATB2 (all whole-slide sections showed expression). Positive SATB2 expression was observed in 11 of 22 (50%) undifferentiated pleomorphic sarcomas (UPSs), and in five of 11 (45%) fibrosarcomas; expression was absent in two pleomorphic rhabdomyosarcomas and in the one leiomyosarcoma. The sensitivity of SATB2 for osteosarcoma was 94%, and the specificity was 55%. Stronger-intensity staining was observed in osteosarcoma (P < 0.0001).

CONCLUSIONS

SATB2 is a sensitive marker for osteosarcoma; however, it is not specific, with expression being observed in other high-grade primary bone sarcomas. Intriguingly, the lack of specificity may suggest that the undifferentiated sarcomas (UPSs and fibrosarcomas) with SATB2 expression actually represent osteosarcomas that produce too little matrix to be detected with routine sampling or consist of osteoblast precursors that do not synthesize matrix.

Development and validation of an app-based cell counter for use in the clinical laboratory setting

Introduction:

For decades cellular differentials have been generated exclusively on analog tabletop cell counters. With the advent of tablet computers, digital cell counters – in the form of mobile applications (“apps”) – now represent an alternative to analog devices. However, app-based counters have not been widely adopted by clinical laboratories, perhaps owing to a presumed decrease in count accuracy related to the lack of tactile feedback inherent in a touchscreen interface. We herein provide the first systematic evidence that digital cell counters function similarly to standard tabletop units.

Methods:

We developed an app-based cell counter optimized for use in the clinical laboratory setting. Paired counts of 188 peripheral blood smears and 62 bone marrow aspirate smears were performed using our app-based counter and a standard analog device. Differences between paired data sets were analyzed using the correlation coefficient, Student's t-test for paired samples and Bland–Altman plots.

Results:

All counts showed excellent agreement across all users and touch screen devices. With the exception of peripheral blood basophils (r = 0.684), differentials generated for the measured cell categories within the paired data sets were highly correlated (all r ≥ 0.899). Results of paired t-tests did not reach statistical significance for any cell type (all P > 0.05), and Bland–Altman plots showed a narrow spread of the difference about the mean without evidence of significant outliers.

Conclusions:

Our analysis suggests that no systematic differences exist between cellular differentials obtained via app-based or tabletop counters and that agreement between these two methods is excellent.

Pharmacokinetics and physiologic effects of alprazolam after a single oral dose in healthy mares

The objective of this study was to evaluate the pharmacokinetic properties and physiologic effects of a single oral dose of alprazolam in horses. Seven adult female horses received an oral administration of alprazolam at a dosage of 0.04 mg/kg body weight. Blood samples were collected at various time points and assayed for alprazolam and its metabolite, α-hydroxyalprazolam, using liquid chromatography/mass spectrometry. Pharmacokinetic disposition of alprazolam was analyzed by a one-compartmental approach. Mean plasma pharmacokinetic parameters (±SD) following single-dose administration of alprazolam were as follows: Cmax 14.76 ± 3.72 ng/mL and area under the curve (AUC0-∞ ) 358.77 ± 76.26 ng·h/mL. Median (range) Tmax was 3 h (1-12 h). Alpha-hydroxyalprazolam concentrations were detected in each horse, although concentrations were low (Cmax 1.36 ± 0.28 ng/mL). Repeat physical examinations and assessment of the degree of sedation and ataxia were performed every 12 h to evaluate for adverse effects. Oral alprazolam tablets were absorbed in adult horses and no clinically relevant adverse events were observed. Further evaluation of repeated dosing and safety of administration of alprazolam to horses is warranted.

Pharmacokinetics and pharmacodynamics of three formulations of firocoxib in healthy horses

The objectives of this study were to compare the pharmacokinetics and COX selectivity of three commercially available formulations of firocoxib in the horse. Six healthy adult horses were administered a single dose of 57 mg intravenous, oral paste or oral tablet firocoxib in a three-way, randomized, crossover design. Blood was collected at predetermined times for PGE2 and TXB2 concentrations, as well as plasma drug concentrations. Similar to other reports, firocoxib exhibited a long elimination half-life (31.07 ± 10.64 h), a large volume of distribution (1.81 ± 0.59L/kg), and a slow clearance (42.61 ± 11.28 mL/h/kg). Comparison of the oral formulations revealed a higher Cmax , shorter Tmax , and greater AUC for the paste compared to the tablet. Bioavailability was 112% and 88% for the paste and tablet, respectively. Maximum inhibition of PGE2 was 83.76% for the I.V. formulation, 52.95% for the oral paste formulation, and 46.22% for the oral tablet formulation. Pharmacodynamic modeling suggests an IC50 of approximately 27 ng/mL and an IC80 of 108 ng/ mL for COX2 inhibition. Inhibition of TXB2 production was not detected. This study indicates a lack of bioequivalence between the oral formulations of firocoxib when administered as a single dose to healthy horses.

Turtle utricle dynamic behavior using a combined anatomically accurate model and experimentally measured hair bundle stiffness

Anatomically correct turtle utricle geometry was incorporated into two finite element models. The geometrically accurate model included appropriately shaped macular surface and otoconial layer, compact gel and column filament (or shear) layer thicknesses and thickness distributions. The first model included a shear layer where the effects of hair bundle stiffness was included as part of the shear layer modulus. This solid model's undamped natural frequency was matched to an experimentally measured value. This frequency match established a realistic value of the effective shear layer Young's modulus of 16 Pa. We feel this is the most accurate prediction of this shear layer modulus and fits with other estimates (Kondrachuk, 2001b). The second model incorporated only beam elements in the shear layer to represent hair cell bundle stiffness. The beam element stiffness's were further distributed to represent their location on the neuroepithelial surface. Experimentally measured striola hair cell bundles mean stiffness values were used in the striolar region and the mean extrastriola hair cell bundles stiffness values were used in this region. The results from this second model indicated that hair cell bundle stiffness contributes approximately 40% to the overall stiffness of the shear layer-hair cell bundle complex. This analysis shows that high mass saccules, in general, achieve high gain at the sacrifice of frequency bandwidth. We propose the mechanism by which this can be achieved is through increase the otoconial layer mass. The theoretical difference in gain (deflection per acceleration) is shown for saccules with large otoconial layer mass relative to saccules and utricles with small otoconial layer mass. Also discussed is the necessity of these high mass saccules to increase their overall system shear layer stiffness. Undamped natural frequencies and mode shapes for these sensors are shown.

Loss of Heterozygosity and Microsatellite Instability Are Rare in Sporadic Dedifferentiated Liposarcoma: A Study of 43 Well-Characterized Cases

Context.—Defects in mismatch repair proteins have been identified in Lynch syndrome–associated liposarcomas, as well as in rare sporadic sarcomas. However, it is unclear if mismatch repair defects have a role in sarcoma tumorigenesis. Microsatellite instability is a surrogate marker of mismatch repair defects.

Objectives.—To determine whether sporadic dedifferentiated liposarcomas display microsatellite instability and, if so, to evaluate whether such instability differs between the lipogenic and nonlipogenic components of these tumors.

Design.—The diagnoses of conventional dedifferentiated liposarcoma were confirmed by a combination of morphologic, immunophenotypic, and molecular studies. Standard fluorescence-based polymerase chain reaction, including 5 mononucleotide microsatellite markers (BAT25, BAT26, NR21, NR24, and MONO27), as well as 2 pentanucleotide repeat markers (Penta C and Penta D), was used to test for instability and loss of heterozygosity.

Results.—We demonstrated only a single case (1 of 43) with microsatellite instability at one mononucleotide marker. No sarcomas showed high-level microsatellite instability. However, loss of heterozygosity at the pentanucleotide markers was observed in 8 of 43 cases. The presence of loss of heterozygosity was overrepresented in the nonlipogenic (dedifferentiated) components compared with the paired lipogenic (well differentiated) components.

Conclusions.—Mismatch repair defects do not contribute to sporadic dedifferentiated liposarcoma tumorigenesis. Whether the observed loss of heterozygosity drives tumorigenesis in liposarcoma, for example by affecting tumor suppressor or cell cycle regulator genes, remains to be determined.

Sex disparities in tuberculosis suspect evaluation: a cross-sectional analysis in rural Uganda

SETTING

Six primary health care centers in rural Uganda.

OBJECTIVE

To compare the quality of tuberculosis (TB) evaluation for men and women presenting to primary health care facilities in high-burden settings.

DESIGN

Cross-sectional study using indicators derived from the International Standards of Tuberculosis Care (ISTC) to compare the quality of TB evaluation services provided to men and women.

RESULTS

Of 161 230 patient visits between January 2009 and December 2010, 112 329 (69.7%) were women. We considered 3308 (2.1%) patients with cough ≥2 weeks as TB suspects, of whom 1871 (56.6%) were women. Female TB suspects were less likely to be referred for sputum smear examination (45.9% vs. 61.6%, P < 0.001), to complete sputum smear examination if referred (73.7% vs. 78.3%, P = 0.024) and to receive comprehensive evaluation and care as defined by the ISTC (33.0% vs. 45.6%, P < 0.001). After adjusting for age, clinic site and visit date, women remained less likely to be referred for sputum smear examination (risk ratio [RR] 0.81, 95%CI 0.74-0.89, P < 0.001) and to receive ISTC-recommended care (RR 0.79, 95%CI 0.72-0.86, P < 0.001).

CONCLUSION

Strategies to ensure that women receive appropriate TB evaluation could provide a valuable opportunity for increasing case detection while also promoting equitable and universal access to care.

Intraocular lymphoma: a clinical perspective

Primary vitreoretinal lymphoma (PVRL) is a rare malignancy that is speculated to arise extraocularly, and preferentially invade and flourish in the ocular and CNS microenvironments. The eye is involved in about 20% of primary central nervous system lymphomas, but the brain is eventually involved in about 80% of PVRL. Most are B-cell lymphomas with small numbers of T-cell lymphomas metastatic to the vitreous and retina. Metastatic systemic B-cell lymphoma usually involves choroid. Primary choroidal lymphoma is rare. Intraocular lymphoma can usually be distinguished from uveitis clinically, although there are overlaps, which may be pronounced in eyes with a large component of reactive inflammation related to tumor surveillance and control. There are controversies in diagnosis and treatment. Diagnosis through examination of ocular fluid is technically difficult and can utilize cytology, immunohistochemistry, flow cytometry, molecular detection of gene rearrangements, and cytokine profiling. Treatment of intraocular lymphoma without detectable CNS disease could consist of a full course of systemic chemotherapy with ocular adjunctive treatment, or ocular treatment alone depending on the preference of the clinical center. In ocular only cases where the vitreous has been debulked to improve vision and there is no sight-threatening involvement of the RPE, orbital irradiation or intravitreal chemotherapy stabilizes the intraocular process but does not seem to modify the CNS component, which can present symptomatically in an advanced state. This is a highly malignant disease with a poor prognosis. Close collaboration with a pathologist and oncologist, and good communication with patients is essential.

A high-field adiabatic fast passage ultracold neutron spin flipper for the UCNA experiment

The UCNA collaboration is making a precision measurement of the β asymmetry (A) in free neutron decay using polarized ultracold neutrons (UCN). A critical component of this experiment is an adiabatic fast passage neutron spin flipper capable of efficient operation in ambient magnetic fields on the order of 1 T. The requirement that it operate in a high field necessitated the construction of a free neutron spin flipper based, for the first time, on a birdcage resonator. The design, construction, and initial testing of this spin flipper prior to its use in the first measurement of A with UCN during the 2007 run cycle of the Los Alamos Neutron Science Center's 800 MeV proton accelerator is detailed. These studies determined the flipping efficiency of the device, averaged over the UCN spectrum present at the location of the spin flipper, to be ̅ε=0.9985(4).

Diagnostic dilemmas in retinitis and endophthalmitis

Visual loss in infectious posterior uveitis or panuveitis can occur if proper therapy is delayed because of diagnostic uncertainty. Some disorders, such as acute retinal necrosis and bacterial endophthalmitis, can be rapidly progressive, and therefore require prompt and accurate diagnosis to guide initial therapy. Other more slowly evolving infections, such as toxoplasmic chorioretinitis or fungal endophthalmitis, can be worsened by empiric use of corticosteroids without specific antimicrobial coverage. Key ocular diagnostic features are helpful but highly variable with overlap with both non-infectious uveitis and neoplastic masquerades, even for key signs such as hypopyon. Close examination of the fundus with attention to color, location, size, border, and opacity of lesions and associated arteriolitis or frosted branch angiitis is helpful in the diagnosis of chorioretinitis. Ultrasonography is an important tool in the evaluation of eyes with suspected endophthalmitis, especially those with intracapsular infection or focal infected deposits. Testing of intraocular fluid can be extremely useful but suffers from inaccessibility, poor sensitivity, and test selections dependent on a presumptive diagnosis, which may be wrong. The dilemma for clinician is to make the correct diagnosis of a rare, blinding, variegated disease quickly enough to intercede with specific therapy or to apply empiric therapy in a sufficiently skilled manner to avert disaster and confirm the diagnosis by response to treatment. When non-infectious uveitis is in the differential, empiric corticosteroids must sometimes be used, at great risk, if clinical examination, ancillary testing, and any available intraocular diagnostic tests have failed to confirm a diagnosis.

Chest radiographic findings of pulmonary tuberculosis in severely immunocompromised patients with the human immunodeficiency virus

OBJECTIVE

We describe chest radiograph (CXR) findings in a population with a high prevalence of human immunodeficiency virus (HIV) and tuberculosis (TB) in order to identify radiological features associated with TB; to compare CXR features between HIV-seronegative and HIV-seropositive patients with TB; and to correlate CXR findings with CD4 T-cell count.

METHODS

Consecutive adult patients admitted to a national referral hospital with a cough of duration of 2 weeks or longer underwent diagnostic evaluation for TB and other pneumonias, including sputum examination and mycobacterial culture, bronchoscopy and CXR. Two radiologists blindly reviewed CXRs using a standardised interpretation form.

RESULTS

Smear or culture-positive TB was diagnosed in 214 of 403 (53%) patients. Median CD4+ T-cell count was 50 cells mm(-3) [interquartile range (IQR) 14-150]. TB patients were less likely than non-TB patients to have a normal CXR (12% vs 20%, p = 0.04), and more likely than non-TB patients to have a diffuse pattern of opacities (75% vs 60%, p = 0.003), reticulonodular opacities (45% vs 12%, p < 0.001), nodules (14% vs 6%, p = 0.008) or cavities (18% vs 7%, p = 0.001). HIV-seronegative TB patients more often had consolidation (70% vs 42%, p = 0.007) and cavities (48% vs 13%, p < 0.001) than HIV-seropositive TB patients. TB patients with a CD4+ T-cell count of ≤ 50 cells mm(-3) less often had consolidation (33% vs 54%, p = 0.006) and more often had hilar lymphadenopathy (30% vs 16%, p = 0.03) compared with patients with CD4 51-200 cells mm(-3).

CONCLUSION

Although different CXR patterns can be seen in TB and non-TB pneumonias there is considerable overlap in features, especially among HIV-seropositive and severely immunosuppressed patients. Providing clinical and immunological information to the radiologist might improve the accuracy of radiographic diagnosis of TB.