Analysis of Dominant HIV Quasispecies Suggests Independent Viral Evolution Within Spinal Granulomas Coinfected with Mycobacterium tuberculosis and HIV-1 Subtype C.

Extrapulmonary tuberculosis (TB) is a significant public health challenge in South Africa and worldwide, largely fuelled by the HIV epidemic. In spinal TB, Mycobacteria infect the spinal column without dissemination to the spinal cord. The immune microenvironment, target cell characteristics, and other evolutionary forces within granulomas during HIV/TB coinfection are poorly characterized. We investigated whether spinal TB granulomas represent a sequestered anatomical site where independent HIV evolution occurs, and assessed the role of macrophages as a target cell for both HIV and mycobacteria. RNA was extracted from plasma and granulomatous tissue from six antiretroviral-naive HIV-1/spinal TB-coinfected patients, RT-PCR amplified, and the C2-V5 env segment was cloned and sequenced. Analysis of genetic diversity, phylogeny and coalescence patterns was performed on clonal sequences. To investigate their role in HIV sequestration, macrophages and the HIV-1 p24 protein were immune localized and ultrastructural features were studied. Intercompartment diversity measurements and phylogenetic reconstruction revealed anatomically distinct monophyletic HIV-1 clusters in four of six patients. Genotypic CCR5-tropic variants were predominant (98.9%) with conservation of putative N-linked glycosylation sites in both compartments. CD68(+) reactivity was associated with higher tissue viral load (r = 1.0; p < 0.01) but not greater intrapatient diversity (r = 0.60; p > 0.05). Ultrastructural imaging revealed the presence of bacterial and virus-like particles within membrane-bound intracellular compartments of macrophages. Spinal tuberculosis granulomas may form anatomically discreet sites of divergent viral evolution. Macrophages in these granulomas harbored both pathogens, suggesting that they may facilitate the process of viral sequestration within this compartment.

Biochemical markers of bone turnover in tibia fracture patients randomly assigned to growth hormone (GH) or placebo injections: Implications for detection of GH abuse.

CONTEXT: It has been argued that increased levels of bone remodelling markers are not suitable indicators of GH abuse, as bone injuries per se increase the expression levels of these markers. OBJECTIVE: To investigate the impact of a recovering tibia fracture on circulating bone markers in subjects receiving placebo or GH treatment. DESIGN AND SETTING: A randomised, double-blind, placebo-controlled trial of up to 16weeks GH treatment, followed by a 16-week washout. PARTICIPANTS AND INTERVENTION: Subjects (406 adult males and females) with a tibia fracture were randomly allocated within three days after surgery, to either placebo or GH treatment (15, 30 or 60µg/kg daily) until fracture healing or 16weeks after treatment initiation. MAIN OUTCOME MEASURES: IGF-I, serum C-terminal telopeptide of type I collagen (CTX), osteocalcin (OST) and bone-specific alkaline phosphatase (BAP) were measured during and after treatment. RESULTS: Dose-dependent increases were observed in groups receiving GH, and mean levels in the highest GH dose group peaked at eight (IGF-I, CTX) or 12weeks (OST) after treatment initiation. Statistically significant differences between GH treatment and placebo were seen for IGF-I, CTX and OST in all GH dose groups throughout the treatment period, and persisted until eight (CTX) or 12 (OST) weeks after cessation of treatment. CONCLUSION: IGF-I, CTX and OST are suitable candidate markers of prolonged, illicit administration of GH. Furthermore, CTX and OST have potentials to serve as markers also after cessation of GH administration.

Recombinant human bone morphogenetic protein-2: a randomized trial in open tibial fractures treated with reamed nail fixation.

BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) improves healing of open tibial fractures treated with unreamed intramedullary nail fixation. We evaluated the use of rhBMP-2 in the treatment of acute open tibial fractures treated with reamed intramedullary nail fixation. METHODS: Patients were randomly assigned (1:1) to receive the standard of care consisting of intramedullary nail fixation and routine soft-tissue management (the SOC group) or the standard of care plus an absorbable collagen sponge implant containing 1.5 mg/mL of rhBMP-2 (total, 12.0 mg) (the rhBMP-2/ACS group). Randomization was stratified by fracture severity. The absorbable collagen sponge was placed over the fracture at wound closure. The primary efficacy end point was the proportion of subjects with a healed fracture as demonstrated by radiographic and clinical assessment thirteen and twenty weeks after definitive wound closure. RESULTS: Two hundred and seventy-seven patients were randomized and were the subjects of the intent-to-treat analysis. Thirteen percent of the fractures were Gustilo-Anderson Type IIIB. The proportions of patients with fracture-healing were 60% and 48% at week 13 (p = 0.0541) and 68% and 67% at week 20 in the rhBMP-2/ACS and SOC groups, respectively. Twelve percent of the subjects underwent secondary procedures in each group; more invasive procedures (e.g., exchange nailing) accounted for 30% of the procedures in the rhBMP-2/ACS group and 57% in the SOC group (p = 0.1271). Infection was seen in twenty-seven (19%) of the patients in the rhBMP-2/ACS group and fifteen (11%) in the SOC group (p = 0.0645; difference in infection risk = 0.09 [95% confidence interval, 0.0 to 0.17]). The adverse event incidence was otherwise similar between the treatment groups. CONCLUSIONS: The healing of open tibial fractures treated with reamed intramedullary nail fixation was not significantly accelerated by the addition of an absorbable collagen sponge containing rhBMP-2.

Effects of growth hormone in patients with tibial fracture: a randomised, double-blind, placebo-controlled clinical trial.

OBJECTIVE: Investigate whether intervention with GH after tibial fracture enhances fracture healing. DESIGN: Randomised, double-blind, placebo-controlled study in 406 patients (93 women, 313 men, age: 18-64 years) with tibial fracture. METHODS: Patients were stratified by tibial fracture (open or closed) and allocated to placebo or GH treatment (15, 30 or 60 mug/kg daily, until clinically assessed healing or until 16 weeks post-surgery). Primary outcome was time from surgery until fracture healing and assessment of healing was done centrally and observer blinded. Patients reported for evaluation every 4 weeks until 24 weeks, and at 9 and 12 months. RESULTS: GH did not accelerate time to healing in the combined group of open and closed fractures. When separately analysing the closed and open fractures, a significant difference in time to healing was observed between treatment groups, exclusively in the closed fractures (P<0.05; subgroup analysis revealed that the 60 microg/kg group was significantly different from placebo). The relative risk of fracture healing for 60 microg/kg versus placebo during the 12 month was: all fractures, 1.16; 95% CI: (0.86; 1.57) (ns); closed fractures, 1.44; 95% CI: (1.01; 2.05; P<0.05); open fractures, 0.75; 95% CI: (0.42; 1.31) (ns). The estimated median number of days before fracture healing in closed fractures was 95 with 60 microg/kg versus 129 with placebo (95% CI: (94; 129) and (94; 249)) corresponding to approximately 26% decrease in healing time. CONCLUSIONS: In the overall group of open and closed tibial fractures, no significant enhancement of fracture healing was observed with GH, whereas in closed tibial fractures, GH accelerated healing significantly.

AO-classification of thoracic and lumbar fractures--reproducibility utilizing radiographs and clinical information.

This study was designed to assess the inter-observer reliability and intra-observer reproducibility of standard radiographic evaluation of 150 thoraco-lumbar fractures using the AO-classification. The influence of clinical information on agreement levels was also evaluated. Six observers (two junior and four senior residents) evaluated the radiographic images. The injuries were classified by each observer as either type A, B or C according to the AO-classification system and the levels of agreement were documented. After 3 months the injuries were again classified with the addition of the clinical findings of each patient and the level of agreement evaluated. The level of agreement was measured using Cohen's kappa-test. The overall inter-observer agreement was rated as fair (0.291) in the first session and moderate (0.403) in the second. Intra-observer values ranged from slight (0.181) to moderate (0.488). The increased level of agreement in the second session was attributed to the value of additional clinical information, the learning curve of the junior residents and the simplicity of the classification.

Recombinant human bone morphogenetic protein-2 for treatment of open tibial fractures: a prospective, controlled, randomized study of four hundred and fifty patients.

BACKGROUND: The treatment of open fractures of the tibial shaft is often complicated by delayed union and nonunion. The objective of this study was to evaluate the safety and efficacy of the use of recombinant human bone morphogenetic protein-2 (rhBMP-2; dibotermin alfa) to accelerate healing of open tibial shaft fractures and to reduce the need for secondary intervention. METHODS: In a prospective, randomized, controlled, single-blind study, 450 patients with an open tibial fracture were randomized to receive either the standard of care (intramedullary nail fixation and routine soft-tissue management [the control group]), the standard of care and an implant containing 0.75 mg/mL of rhBMP-2 (total dose of 6 mg), or the standard of care and an implant containing 1.50 mg/mL of rhBMP-2 (total dose of 12 mg). The rhBMP-2 implant (rhBMP-2 applied to an absorbable collagen sponge) was placed over the fracture at the time of definitive wound closure. Randomization was stratified by the severity of the open wound. The primary outcome measure was the proportion of patients requiring secondary intervention because of delayed union or nonunion within twelve months postoperatively. RESULTS: Four hundred and twenty-one (94%) of the patients were available for the twelve-month follow-up. The 1.50-mg/mL rhBMP-2 group had a 44% reduction in the risk of failure (i.e., secondary intervention because of delayed union; relative risk = 0.56; 95% confidence interval = 0.40 to 0.78; pairwise p = 0.0005), significantly fewer invasive interventions (e.g., bone-grafting and nail exchange; p = 0.0264), and significantly faster fracture-healing (p = 0.0022) than did the control patients. Significantly more patients treated with 1.50 mg/mL of rhBMP-2 had healing of the fracture at the postoperative visits from ten weeks through twelve months (p = 0.0008). Compared with the control patients, those treated with 1.50 mg/mL of rhBMP-2 also had significantly fewer hardware failures (p = 0.0174), fewer infections (in association with Gustilo-Anderson type-III injuries; p = 0.0219), and faster wound-healing (83% compared with 65% had wound-healing at six weeks; p =0.0010). CONCLUSIONS: The rhBMP-2 implant was safe and, when 1.50 mg/mL was used, significantly superior to the standard of care in reducing the frequency of secondary interventions and the overall invasiveness of the procedures, accelerating fracture and wound-healing, and reducing the infection rate in patients with an open fracture of the tibia.

The outcome of allografts and anterior instrumentation in spinal tuberculosis.

Spinal tuberculosis is the most common form of osteoarticular tuberculosis. Fractures, slippage, and increasing deformity have been reported with the use of autologous rib grafts after anterior spinal decompression. Forty-one patients with neurologic deficits caused by spinal tuberculosis had radical anterior decompression, and the anterior column was reconstructed with fresh-frozen femoral allografts and stabilized with a single-rod screw construct. Antituberculous therapy was administered for 12 months and complete neurologic recovery occurred in 32 patients. The incorporation of allografts commenced between 12 and 18 months. Fusion and remodeling was observed in 33 patients and partial remodeling with fusion was observed in eight patients at a mean followup of 6.4 years. Forty-two percent correction of the kyphosis was achieved and there were no cases of fracture or late sepsis. Fresh-frozen allografts and anterior instrumentation are superior to rib grafts in supporting the anterior spinal column, and although fusion occurred late, the grafts remained stable.