Estimation of urinary neutrophil-gelatinase associated lipocalin may be useful as a noninvasive diagnostic or prognostic biomarker for renal scarring.

Monitoring of active human herpesvirus 6 (HHV-6) infection is important for distinguishing between reactivation and latency of the virus. The reverse transcription polymerase chain reaction (RT-PCR) may be a useful tool in order to distinguish active and latent HHV-6 infection. An RT-PCR assay detecting 4 different HHV-6 gene transcripts was established. Samples of peripheral blood mononuclear cells (PBMCs) were collected from patients with exanthem subitum and used to evaluate the reliability of the assay. After confirming the reliability of the assay, RT-PCR was used to determine whether HHV-6 reactivation occurs in children with hypercytokinemia. Three gene transcripts (U31, U39, and U94) were detected in 90-100% of the PBMC samples collected from febrile period of exanthem subitum patients, from which HHV-6 was isolated. The two gene transcripts encoding the late proteins U31 and U39, however, were not detected in samples collected during the convalescent period that contained no infectious virus. The putative latency associated gene transcript, U94, was detected in 2 (10%) of the 20 convalescent samples, and another immediate early gene transcript, U90, was also detected in 3 (15%) of the 20 convalescent samples. The frequency of HHV-6 reactivation in patients with hypercytokinemia, suggesting monocyte/macrophage activation, was studied. Only 9 of 17 patients diagnosed with Kawasaki disease and 1 patient diagnosed with juvenile rheumatoid arthritis were positive for HHV-6 DNA in their PBMCs samples. Neither the U31 gene nor the U94 gene transcript was detected in any of the 10 samples. An RT-PCR assay screening for both immediate early and late genes may be useful for monitoring active HHV-6 infection. No HHV-6 reactivation was found in patients with hypercytokinemia using the RT-PCR assay.

Cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and 7 (HHV-7) are important pathogens in immunocompromised patients. To elucidate the kinetics of the three β-herpesviruses in saliva and urine samples were collected serially from children with renal diseases. Twenty children with renal diseases were enrolled in this study. A total of 240 saliva and urine samples were collected monthly from the patients over a 1-year period. Viral DNAs loads were measured by real-time PCR. In 10 CMV seropositive patients CMV DNA was detected rarely in saliva and CMV DNA load was lower than the other two β-herpesviruses DNA loads. All patients were seropositive for HHV-6B and the virus was detected frequently in saliva. Two of 20 patients were HHV-7 seronegative. High copies of viral DNA were detected continuously in saliva of the HHV-7 seropositive patients. Although neither CMV nor HHV-6B DNA load was different among the three renal diseases, HHV-7 DNA load was different among the diseases (P = 0.039). HHV-6B DNA loads were significantly higher in patients with immunosuppressive treatment compared to those without treatment (P = 0.013). Although CMV DNA was detected in urine samples collected from 5 of 10 CMV seropositive patients, HHV-6B and HHV-7 DNA were detected at relatively low frequencies in urine. No remarkable temporal associations between viral DNA excretion and proteinuria or immunosuppressive treatment were demonstrated. The pattern of viral DNA excretion in saliva and urine were different among the three viruses. No temporal correlation was observed between viral infection and renal diseases.

Rotavirus gastroenteritis causes substantial morbidity and mortality worldwide in children. We report three infants with rotavirus gastroenteritis complicated by various severity of gastrointestinal bleeding. Two patients (cases 1 and 2) recovered completely without any specific treatments. One patient (case 3) died despite extensive treatments including a red blood cell transfusion and endoscopic hemostatic therapy. Rotavirus genotypes G1P[8] and G9P[8] were detected in cases 2 and 3, respectively. Rotavirus antigenemia levels were not high at the onset of melena, suggesting that systemic rotaviral infection does not play an important role in causing melena.

Five patients suffering from exanthem subitum with thrombocytopenia were confirmed as primary human herpesvirus 6 (HHV‐6) infection by serological test. All cases had thrombocytopenia during the acute phase of exanthem subitum. The clinical features of these cases were benign, and all recovered without any specific treatment. Moreover. 4 of the 5 cases showed a mild elevation of hepatic transaminase during the same period, and other viral infections including cytomegalovirus, Epstein‐Barr virus, and human herpesvirus 7 were ruled out in these patients. It was speculated that direct inhibition of platelet production by the virus or cytokine induced by the virus‐infected cells was the mechanism of the thrombocytopenia induced by primary HHV‐6 infection.