Ridascreen

Blood tests for measuring peripheral WBC counts, and CRP, LDH, and mycoplasma IgM antibody levels were performed on admission. A blood test for measuring mycoplasma IgM antibody level was performed within 7 days after admission for diagnosing MPP.
A serum sample for PCT level determination was collected on admission and stored at -20°C until analyzed. Serum PCT level was measured on a Roche Cobas e601 analyzer based on an electrochemiluminescence immunoassay using the Elecsys BRAHMS PCT kit (Roche Diagnostics Korea, Seoul, Korea). The assay detection range was 0.02–100 ng/mL.
Serum mycoplasma IgM level was assayed using an enzyme immunoassay (RIDASCREEN; R-Biopharm AG, Darmstadt, Germany). The cutoff level for mycoplasma IgM antibody level was 71 U/mL. Mycoplasma PCR of sputum or nasopharyngeal aspiration samples was performed using the Bio-Core M. pneumoniae PCR Kit (Seegene, Seoul, Korea). The mycoplasma PCR was performed in 2 patients, and those patients showed positive results in both PCR and serology tests. PCR was not performed in the remaining patients, and the diagnosis was established using the enzyme immunoassay (EIA) method.

Inductively coupled plasma mass spectrometry analysis was used to quantify concentrations of quantity elements (Na, Mg, P, K, and Ca), essential trace elements (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Mo, and I), and heavy metals (Cd, Hg, and Pb) in milk and serum. For measurement of vitamin B₁₂ in undiluted milk, a commercial competitive assay (RIDAscreen, R-Biopharm) was used. Analyses were carried out according to the methods previously published by our group (Denholm et al., 2019 (link)).