Providing an Evidence Base for Tissue Sampling and Culture Interpretation in Suspected Fracture-Related Infection.

BACKGROUND: The recent consensus definition for the diagnosis of fracture-related infection (FRI) includes the identification of indistinguishable microorganisms in at least 2 surgical deep-tissue specimens as a confirmatory criterion. However, this cut-off, and the total number of specimens from a patient with suspected FRI that should be sent for microbiological testing, have not been validated. We endeavored to estimate the accuracy of different numbers of specimens and diagnostic cut-offs for microbiological testing of deep-tissue specimens in patients undergoing surgical treatment for possible FRI. METHODS: A total of 513 surgical procedures in 385 patients with suspected FRI were included. A minimum of 2 surgical deep-tissue specimens were submitted for microbiological testing; 5 or more specimens were analyzed in 345 procedures (67%). FRI was defined by the presence of any confirmatory criteria other than microbiology. Resampling was utilized to model the sensitivity and specificity of diagnostic cut-offs for the number of surgical specimens yielding indistinguishable microorganisms and for the total number of specimens. The likelihood of detecting all clinically relevant microorganisms was also assessed. RESULTS: A diagnostic cut-off of at least 2 of 5 specimens with indistinguishable microorganisms identified by culture was 68% sensitive (95% confidence interval [CI], 62% to 74%) and 87% specific (95% CI, 81% to 94%) for the diagnosis of FRI. Two out of 3 specimens were 60% sensitive (95% CI, 55% to 66%) and 92% specific (95% CI, 88% to 96%). Submitting only 3 deep-tissue specimens risked missing clinically relevant microorganisms in at least 1 in 10 cases. CONCLUSIONS: The present study was the first to validate microbiological criteria for the diagnosis of FRI, supporting the current confirmatory diagnostic criteria for FRI. Analysis of at least 5 deep-tissue specimens in patients with possible FRI is recommended. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clofazimine for Treatment of Cryptosporidiosis in Human Immunodeficiency Virus Infected Adults: An Experimental Medicine, Randomized, Double-blind, Placebo-controlled Phase 2a Trial.

BACKGROUND: We evaluated the efficacy, pharmacokinetics (PK), and safety of clofazimine (CFZ) in patients living with human immunodeficiency virus (HIV) with cryptosporidiosis. METHODS: We performed a randomized, double-blind, placebo-controlled study. Primary outcomes in part A were reduction in Cryptosporidium shedding, safety, and PK. Primary analysis was according to protocol (ATP). Part B of the study compared CFZ PK in matched individuals living with HIV without cryptosporidiosis. RESULTS: Twenty part A and 10 part B participants completed the study ATP. Almost all part A participants had high viral loads and low CD4 counts, consistent with failure of antiretroviral (ARV) therapy. At study entry, the part A CFZ group had higher Cryptosporidium shedding, total stool weight, and more diarrheal episodes compared with the placebo group. Over the inpatient period, compared with those who received placebo, the CFZ group Cryptosporidium shedding increased by 2.17 log2 Cryptosporidium per gram stool (95% upper confidence limit, 3.82), total stool weight decreased by 45.3 g (P = .37), and number of diarrheal episodes increased by 2.32 (P = .87). The most frequent solicited adverse effects were diarrhea, abdominal pain, and malaise. One placebo and 3 CFZ participants died during the study. Plasma levels of CFZ in participants with cryptosporidiosis were 2-fold lower than in part B controls. CONCLUSIONS: Our findings do not support the efficacy of CFZ for the treatment of cryptosporidiosis in a severely immunocompromised HIV population. However, this trial demonstrates a pathway to assess the therapeutic potential of drugs for cryptosporidiosis treatment. Screening persons living with HIV for diarrhea, and especially Cryptosporidium infection, may identify those failing ARV therapy. CLINICAL TRIALS REGISTRATION: NCT03341767.

Extreme angle, tip-tilt MEMS micromirror enabling full hemispheric, quasi-static optical coverage.

Beam steering is essential for a variety of optical applications such as communication, LIDAR, and imaging. Microelectromechanical system (MEMS) mirrors are an effective method of achieving modest speeds and angular range at low cost. Typically there are a number of tradeoffs considered when designing a tip-tilt mirror, such as tilt angle and speed. For example, many mirrors are designed to scan at their resonant frequency to achieve large angles. This is effective for a scanning mode; however, this makes the device slow and ineffective as a galvo (quasi-static). Here, we present a magnetic MEMS mirror with extreme quasi-static mechanical tilt angles of ±60° (±120° optical) about two rotation axes. This micromirror enables full hemispheric optical coverage without compromising speed; settling in 4.5 ms using advanced drive techniques. This mirror will enable new applications for MEMS micromirrors previously thought impossible due to their limited angular range and speed.

Multiple alleles of Treponema pallidum repeat gene D in Treponema pallidum isolates.

Two new tprD alleles have been identified in Treponema pallidum: tprD2 is found in 7 of 12 T. pallidum subsp. pallidum isolates and 7 of 8 non-pallidum isolates, and tprD3 is found in one T. pallidum subsp. pertenue isolate. Antibodies against TprD2 are found in persons with syphilis, demonstrating that tprD2 is expressed during infection.

Repeated Chlamydia trachomatis infection of Macaca nemestrina fallopian tubes produces a Th1-like cytokine response associated with fibrosis and scarring.

Chlamydia trachomatis-associated female infertility and ectopic pregnancy are caused by postinflammatory fibrosis and scarring of the upper genital tract. Scarring of the upper genital tract is associated with multiple infectious episodes with C. trachomatis. To study the immune response that occurs with multiple infections of C. trachomatis in the female upper genital tract, a Macaca nemestrina model was used. Subcutaneous pockets containing autologous salpingeal tissue implants were inoculated three times with C. trachomatis. The inflammation after three inoculations was associated with a mononuclear infiltrate dominated by CD8 T-cell lymphocytes. Perforin mRNA was induced in infected pockets, demonstrating that activated cytolytic lymphocytes were present in the lesions. Fibrosis, as evidenced by fibroblast proliferation and connective tissue deposition, was observed by the third infection. Cytokine mRNAs induced by repeated chlamydial infection included gamma interferon, interleukin-2 (IL-2), IL-6, and IL-10 mRNAs, but IL-4 mRNA was not induced. Nearly identical findings were found in macaque fallopian tubes infected in situ repeatedly with C. trachomatis, validating the subcutaneous pocket model of chlamydial salpingitis. However, it was not possible to evaluate if there was an induction of perforin mRNA in infected salpingeal tubes in situ, because there was a high basal level of perforin mRNA in these tissues. These results suggest that repeated chlamydial infection of the female upper genital tract leads to CD8 T-cell predominance, a Th1-like cytokine milieu, and these inflammatory changes are associated with progression to fibrosis associated with female infertility.

Analysis of lymphocyte phenotype and cytokine activity in the inflammatory infiltrates of the upper genital tract of female macaques infected with Chlamydia trachomatis.

Chlamydia trachomatis infects the upper genital tract of millions of women, causing infertility and pelvic inflammatory disease, yet the inflammatory response to C. trachomatis infection is poorly understood. The cytokine response and the phenotype of infiltrating lymphocytes during C trachomatis infection of fimbria and ampulla autografts in subcutaneous pockets in Macaca nemestrina were characterized. About two-thirds of the infiltrating lymphocytes were CD8 T cells, with the remainder being CD4 T cells and B cells. Interleukin (IL)-2, IL-6, IL-10, interferon-gamma (IFN-gamma), and perforin mRNA were produced by the infiltrating cells, but IL-4 mRNA was absent. The presence of CD8 T cells and perforin mRNA suggest that activated cytolytic T cells are present. The presence of IL-2 and IFN-gamma mRNA and the absence of IL-4 mRNA suggest that Th1-type cytokines predominate during the acute phase of C. trachomatis infection of the upper genital tract.

Lesions of primary and secondary syphilis contain activated cytolytic T cells.

This study demonstrates that CD8+ cytotoxic lymphocytes (CTL) are found in both primary and secondary syphilis lesions. CD8+ T cells were detected by immunohistology, and mRNAs for granzyme B and perforin were detected by reverse transcription and PCR, suggesting that CD8+ cytotoxic lymphocytes are activated.

Primary and secondary syphilis lesions contain mRNA for Th1 cytokines.

Phagocytosis of Treponema pallidum by cytokine-activated macrophages aids bacterial clearance and lesion resolution in early syphilis. To investigate the cytokine profiles of cells infiltrating primary and secondary syphilis lesions, reverse transcription and polymerase chain reaction (RT-PCR) were used to detect cytokine mRNA in 13 lesion biopsies. Both primary and secondary lesions contained mRNA encoding interleukin (IL)-2, interferon-gamma (IFN-gamma), IL-12p40, and IL-10. In contrast to a lesion from a patient with recurrent herpes simplex virus type 2, no message for IL-4 could be detected in any of the syphilis lesions, and 10 of 13 had no mRNA for IL-5 or IL-13. These findings are consistent with a Th1-predominant local cellular response activating macrophages and support the hypothesis that IFN-gamma-activated macrophages are primary effectors in treponeme clearance.