Kazuo Tsuzuki

A prospective study of human herpesvirus-6 infection in renal transplantation

Sixty-five kidney transplant recipients and their (22 living related and 43 cadaveric) donors were studied prospectively to determine the relationship between kidney transplantation and human herpesvirus-6 (HHV-6) infection. The virus isolation from peripheral blood and other tissues and sequential determination of neutralizing antibodies to HHV-6 were performed during 3 months following the transplantation. All of the donors and their recipients examined had neutralizing antibodies to HHV-6 at the time of renal transplantation and the virus was not isolated from them. HHV-6 was isolated from 3 renal tissues (2 living related and 1 cadaveric) obtained during transplant surgery, but not from their blood at that time. HHV-6 viremia occurred in 9 (14%) of the 65 recipients around 2 to 4 weeks after the transplantation. An additional 27 recipients showed a significant rise in the antibody titer. Thus, the infection with HHV-6 was confirmed in 36 (55%) of the 65. These results indicate that the virus is activated in many cases in the early posttransplant period and that HHV-6 establishes in vivo latency in the kidney tissue. There was no correlation between HHV-6 infection and acute rejection or the antirejection prophylaxis.

Influenza A virus encephalopathy with symmetrical thalamic lesions

Abstract During an epidemic of influenza A infection in Japan, a 7-year-old boy was admitted to our hospital because of high fever, convulsions, coma, and liver dysfunction on the 2nd day of a cold-like illness. His serum CPK was markedly elevated, but there was no hyperammonaemia or hypoglycaemia. His CSF showed an increased protein level, but the cell count and glucose level were normal. CT and MRI of the brain showed symmetrical thalamic lesions, and he was diagnosed with acute necrotizing encephalopathy in childhood. He had a significant increased in antibodies to influenza A H1N1 in serum and CSF, but the CSF was negative for influenza virus using virus isolation and a polymerase chain reaction assay. Conclusion Antibody production without detectable levels of influenza virus in cerebrospinal fluid suggests that virus infection occurred, but the virus did not replicate in sufficient numbers in his central nervous system. The thalamic lesion, the hallmark of acute necrotizing encephalopathy in childhood, may be initiated by a local virus infection and develop with subsequent local changes such as breakdown of the blood-brain barrier and the extravasation of blood.

Role of mizoribine in renal transplantation

Renal transplantation is the optimal form of therapy for children and adolescents with end‐stage renal disease. Usually histocompatibility differences exist between donor and recipient, so it is necessary to modify or suppress the immune response to enable the recipient to accept a graft. Calcineurin inhibitors (CNI), which include cyclosporin (CsA) and tacrolimus (FK506), give many benefits on the outcome after renal transplantation, but have some toxic effects, especially nephrotoxicity. Therefore, inhibitors of purine synthesis revived as newer generation of more specific inhibitors, mizoribine (MZ) and mycophenolate mofetil (MMF). The Japanese pediatric renal transplantation clinical study group attempted to reduce and then discontinue steroid administration in combination with another three immunosuppressive drugs, CsA, MZ and anti‐lymphocyte globurin (ALG). This study showed good clinical results. Mizoribine is an effective immunosuppressive drug in human renal transplantaton. However, it is not as popular as other inhibitors of purine synthesis, such as azathioprine (AZA) and MMF, because MZ has been used mainly in Japan and infrequently in other countries. However, MZ is a more useful immunosuppressive drug than AZA, when it is used in combination with CNI.

Kidney Transplantation From an Anencephalic Baby: A Case Report

We report on a child in whom kidneys from an anencephalic neonate were transplanted. The transplanted kidneys were rejected after they had been functioning well for 2 months.

Twenty-four hour monitoring of blood pressure and heart rate in patients with chronic renal failure or renal transplant recipients: Analysis by the cosinor method

Hypertension is a major problem of patients with chronic renal failure or renal transplant recipients. To clarify the characteristics of blood pressure, heart rate, and circadian rhythms of these patients we used an ambulatory blood pressure monitor (ABPM) for 24 h monitoring and analyzed the data by the cosinor method. In eight chronic renal failure patients without dialysis the midline estimating statistic of rhythm (MESOR) of diastolic blood pressure was higher than in controls, but the MESOR of systolic blood pressure was not. Of 11 patients on dialysis some had hypertension and some had hypotension. In 14 renal transplant recipients, especially those with chronic graft rejection, the MESOR of systolic and diastolic pressures were higher than controls, and the increase of blood pressure MESOR had a significant correlation with the elevation of serum creatinine levels. Circadian rhythms of blood pressure were frequently absent in the patients on dialysis, but circadian rhythms of heart rate were not. The use of an ABPM is a non‐invasive method to monitor patients and allowed us to know changes of blood pressure and heart rate in the daytime as well as during the night. For the control of hypertension in chronic renal failure, monitoring with an ABPM seems to provide invaluable information.

Final height in a prospective trial of late steroid withdrawal after pediatric renal transplantation treated with cyclosporine and mizoribine

Motoyama O, Hasegawa A, Aikawa A, Shishido S, Honda M, Tsuzuki K, Kinukawa T, Hattori M, Ogawa O, Yanagihara T, Saito K, Takahashi K, Ohshima S. Final height in a prospective trial of late steroid withdrawal after pediatric renal transplantation treated with cyclosporine and mizoribine. 
Pediatr Transplantation 2012: 16: 78–82.