title: Superiority of the buffy coat over serum or plasma for the detection of Alkhumra virus RNA using real time RT-PCR.
abstract: RT-PCR to detect Alkhumra virus (ALKV) RNA in plasma or serum has been the standard practice to confirm this infection in the first seven days of illness. In this study, RT-PCR detection of viral RNA from the plasma, serum, and buffy coat (BC) was compared to virus isolation. Plasma, serum, and BC were obtained from seven patients with clinically suspected ALKV infection in Najran, Saudi Arabia. Baby hamster kidney (BHK-21) and rhesus monkey kidney (LLC-MK2) cell culture monolayers were used for virus isolation. Real-time RT-PCR was used to confirm ALKV infection and to detect viral RNA directly from plasma, serum, and BC. ALKV was isolated from five of the seven patients. The virus was isolated from all three specimen types (plasma, serum, and BC) of the five confirmed patients. ALKV RNA was detected directly by RT-PCR in BC in all five (100%) culture-positive patients and in plasma or serum in only four (80%) of the five patients. Three of the five patients for whom ALKV RNA was detected in BC also had detectable viral RNA in plasma and serum. In the remaining two patients with detectable ALKV RNA in the BC, the plasma was positive but the serum was negative in one patient, whereas the serum was positive and the plasma was negative in the other patient. The use of real-time RT-PCR to detect ALKV RNA in the BC was superior to using plasma and serum and equivalent to virus isolation.
authors.affiliation: Department of Medicine, Faculty of Medicine, King Abdulaziz University, P.O. Box 80215, Jeddah 21589, Saudi Arabia. tmadani@kau.edu.sa
authors.forename: Tariq A
authors.initials: TA
authors.lastname: Madani
authors.forename: El-Tayeb M  E
authors.initials: el-TM
authors.lastname: Abuelzein
authors.forename: Esam I
authors.initials: EI
authors.lastname: Azhar
authors.forename: Moujahed
authors.initials: M
authors.lastname: Kao
authors.forename: Hussein M  S
authors.initials: HM
authors.lastname: Al-Bar
authors.forename: Huda
authors.initials: H
authors.lastname: Abu-Araki
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Ksiazek
mesh_terms: D000328:Adult; D000818:Animals; D058621:Blood Buffy Coat / Q000737:chemistry / Q000821:virology*; D002460:Cell Line; D006224:Cricetinae; D005260:Female; D005416:Flavivirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D018177:Flavivirus Infections / Q000097:blood / Q000175:diagnosis / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D055815:Young Adult
chemical_list: D012367:RNA, Viral