Screening for parvovirus B19 antigen through chemiluminescent enzyme immunoassay is equivalent to B19 nucleic acid amplification test-based screening of pooled plasma.

BACKGROUND: Human parvovirus B19 (B19) is a pathogen that threatens the quality of plasma products. Therefore, health authorities have mandated measures against B19 contamination of plasma pools. The US FDA has recommended a B19 genome level of 104 IU/ml or lower in pooled plasma lots. Therefore, the B19 nucleic acid amplification test (B19-NAT) has been introduced in many plasma fractionators. However, in the Japanese Red Cross, which is the only approved blood collector in Japan, the B19 antigen test has been introduced for screening donated blood in Japan. Therefore, to clarify whether the antigen test is robust enough to screen blood samples according to the FDA recommendation, we evaluated B19 genome levels in each pooled plasma lot from 2003 to 2020. STUDY DESIGN AND METHODS: Data of 5576 pooled plasma lots from factories A and B, which were derived from plasma bags and passed the B19 antigen-based tests, receptor-mediated hemagglutination assay (B19-RHA), or chemiluminescent enzyme immunoassay (B19-CLEIA), during 2003 to 2020, were evaluated. The amount of B19 genome in each lot was determined using quantitative or semiquantitative B19-NAT. RESULTS: The B19 genome levels in pooled plasma lots screened using B19-RHA did not meet the FDA recommendation, whereas the lots derived from B19-CLEIA fulfilled the FDA recommendation, even during the B19 epidemic in Japan. DISCUSSION: The results suggest that the B19-CLEIA donor screening for plasma pools is also useful in light of the US FDA recommendation.

[A case of pleural tuberculoma with intra-pulmonary invasion during anti-tuberculosis therapy].

A 27-year-old woman who had been treated for pulmonary tuberculosis with anti-tuberculosis drugs for three months was admitted to our hospital because of pain in the chest and back. Chest CT showed improvement in the pulmonary tuberculosis lesions in the right middle lobe and S8, but there was a large pleural mass in the right lower lung field. Histopathological findings of the percutaneous biopsy showed epithelioid cell granulomas that were negative for acid-fast bacilli. We diagnosed the mass as pleural tuberculoma with intrapulmonary invasion. The pleural tuberculoma improved without any additional therapy.

[Two cases of pulmonary amebiasis].

CASE 1: A 74-year-old man having a week's fever and diagnosed with a liver abscess was treated with several antibiotics and percutaneous liver drainage. His respiration gradually worsened and chest computed tomography (CT) showed right pleural effusion and a left-lung mass. Percutaneous fine needle aspiration of the pulmonary mass detected Entamoeba histolytica. CASE 2: A 44-year old, zoo office worker admitted for fever and right chest pain was found in CT to have right pleural effusion and a mass with a liver abscess necessitating abscess drainage. Injected contrast medium detected a fistula connected to the right. Following surgical drainage, E. histolytica was detected from the resected lung. Both cases responded well to metronidazole.

[A case of drug-induced interstitial pneumonia due to phenytoin].

A 48-year-old woman had been given phenytoin for prevention of epilepsy for 30 years. She developed a dry cough and low grade fever from one year and half before admission to our hospital. During this interval, she was treated with various antibiotics, however, her condition did not improve. A chest radiograph and CT showed diffuse reticular ground glass opacities in bilateral lung fields. A drug lymphocyte stimulation test (DLST) for phenytoin showed positive results. Lung biopsy specimen by VATS revealed predominant lymphocytic infiltration of lung parenchyma, compatible with drug-induced pneumonitis. Administration of phenytoin was discontinued, oral administration of 30 mg prednisolone was initiated, and the symptoms and shadow on X-ray films improved. These observations strongly suggested the presence of drug-induced pneumonia due to phenytoin in this patient. In patients who develop pneumonia not associated with infection, the possibility of drug-induced pneumonia should be always considered even though the drug has been administered for a long period.