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Abstract Multiplex assays for malaria antigen detection can gather data from large sample sets, but considerations for the consistency and quality assurance (QA) of mass testing lack evaluation. We present a QA framework for a study occurring November 2019 to March 2020 involving 504 assay plates detecting four Plasmodium antigens: pan-Plasmodium aldolase and lactate dehydrogenase (LDH), histidine-rich protein 2 (HRP2), P. vivax LDH (PvLDH). Controls on each plate included buffer blank, antigen negative blood, and 4-point positive dilution curve. The blank and negative blood provided consistently low signal for all targets except for pAldolase, which showed variability. Positive curve signals decreased throughout the 5-month study duration but retained a coefficient of variation (CV) of

Imaging of metastatic castrate-resistant prostate cancer to select patients suitable for peptide receptor radioligand therapy can be performed with both SPECT and PET PSMA radiotracers. Although PET radiotracers generally have higher sensitivity and spatial resolution, SPECT tracers can be an effective alternative when PET/CT systems are unavailable in the clinical setting. We present a case of a 43-year-old male, who was referred to our facility for workup for radioligand PSMA therapy. His Tc-99m PSMA images revealed diffuse bone infiltration in a pattern mimicking a bone scan., Competing Interests: Competing InterestEvbuomwan Osayande, Fourie Carika, and Engelbrecht Gerrit declare that they have no competing interests., (© The Author(s), under exclusive licence to Korean Society of Nuclear Medicine 2022.)

Serosurveillance can provide estimates of population-level exposure to infectious pathogens and has been used extensively during the COVID-19 pandemic. Simultaneous, serological testing for multiple pathogens can be done using bead-based immunoassays to add value to disease-specific serosurveys. We conducted a validation of four SARS-CoV-2 antigens-full-length spike protein, two receptor binding domain proteins, and the nucleocapsid protein-on our existing multiplex bead assay (MBA) for enteric diseases, malaria, and vaccine preventable diseases. After determining the optimal conditions for coupling the antigens to microsphere beads, the sensitivity and specificity of the assay were determined on two instruments (Luminex-200 and MAGPIX) when testing singly (monoplex) versus combined (multiplex). Sensitivity was assessed using plasma from 87 real-time reverse transcription polymerase chain reaction (rRT-PCR) positive persons collected in March-May of 2020 and ranged from 94.3% to 96.6% for the different testing conditions. Specificity was assessed using 98 plasma specimens collected prior to December 2019 and plasma from 19 rRT-PCR negative persons and ranged from 97.4% to 100%. The positive percent agreement was 93.8% to 97.9% using 48 specimens collected > 21 days post-symptom onset, while the negative percent agreement was ≥ 99% for all antigens. Test performance was similar using monoplex or multiplex testing. Integrating SARS-CoV-2 serology with other diseases of public health interest could add significant value to public health programs that have suffered severe programmatic setbacks during the COVID-19 pandemic.

Multiplex assays for malaria antigen detection can gather data from large sample sets, but considerations for the consistency and quality assurance (QA) of mass testing lack evaluation. We present a QA framework for a study occurring November 2019 to March 2020 involving 504 assay plates detecting four Plasmodium antigens: pan-Plasmodium aldolase and lactate dehydrogenase (LDH), histidine-rich protein 2 (HRP2), P. vivax LDH (PvLDH). Controls on each plate included buffer blank, antigen negative blood, and 4-point positive dilution curve. The blank and negative blood provided consistently low signal for all targets except for pAldolase, which showed variability. Positive curve signals decreased throughout the 5-month study duration but retained a coefficient of variation (CV) of < 5%, with the exception of HRP2 in month 5 (CV of 11%). Regression fittings for inter-plate control signals provided mean and standard deviations (SDs), and of 504 assay plates, 6 (1.2%) violated the acceptable deviation limits and were repeated. For the 40,272 human blood samples assayed in this study, of 161,088 potential data points (each sample × 4 antigens), 160,641 (99.7%) successfully passed quality checks. The QA framework presented here can be utilized to ensure quality of laboratory antigen detection for large sample sets.

Background: A testis located outside the scrotum is prone to a lot of complications but early detection and correction give good result. The purpose of this study was to determine the pattern of presentation, complications recorded, the surgical treatment offered and outcome in a developing country., Patients and Methods: A retrospective study of patients that presented with undescended testes at the University of Benin Teaching Hospital between January, 1997 and December, 2006., Results: A total of 76 orchidopexies and 10 orchidectomies were done on 71 patients with undescended testes during the period. They were aged 9 months and 47 years (mean 8.3 +/- 7.9 years) at surgery. Only 31 (43.7%) patients presented at age 5 years and below while 40 (56.3%) presented after 5 years. Seventy-two (83.7%) testes were palpable, ultrasound scan was used to locate 10 (11.6%), while 4 (4.7%) could only be located during groin exploration. Intraoperative assessment of the testes were 54 (62.8%) normal testicular volume, 22 (25.6%) reduced volume and 10 (11.6%) atretic. All those aged 5 years and below had normal/reduced testicular volume and all had orchidopexy whereas those above 5 years with normal/reduced testicular volume had orchidopexy and those with atretic testis had orchidectomy. Post operatively, testicular growth was recorded only among the pre/pubertile boys, the testes retracted in two patients, scrotal skin infection in one, and intra scrotal haematoma in two., Conclusion: Delayed presentation resulted in morphological changes, increased complications, number of orchidectomy and reduced chance of testicular growth post orchidopexy.