posterior reversible encephalopathy syndrome ( pres ) was first described as a distinct clinico - radiological entity by hinchey et al . in 1996 . calcineurin inhibitors ( cyclosporine and tacrolimus ) , high - dose steroid therapy , intravenous immunoglobulin , and sirolimus have been implicated . the overall incidence of pres was 0.49% amongst 4,222 solid organ transplant recipients from 1998 to 2006 in the usa . typical magnetic resonance imaging ( mri ) features are bilateral symmetrical brain edema in the cortical and subcortical regions of the parietal and occipital lobes . treatment strategy is temporary or permanent withdrawal of immunosuppression along with good control of blood pressure . however , immunosuppression withdrawal can be detrimental and in fact , it may need to be intensified as highlighted in our case , due to concomitant acute rejection of the allograft . a 16 year - old male with end - stage renal disease of unknown cause had a living - related renal allograft surgery . tacrolimus and mycophenolic acid ( mpa ) were started pre - transplant ( day - 3 ) and prednisolone was added from day 0 of transplant . serum creatinine was low at 1.1 mg / dl on day 4 . on day 6 the tacrolimus trough level was 2.5 ng / ml . renal doppler showed good perfusion of the graft and no evidence of renal artery stenosis . renal biopsy was deferred because of uncontrolled blood pressure and intravenous ( iv ) methylprednisolone 1 g was empirically given on day 7 for probable acute cellular rejection , after stabilizing systolic blood pressure to 140 mmhg , along with an increase in tacrolimus dose to 3 mg twice daily ( 0.23 mg / kg / day ) . six hours later , he had sudden acceleration of systolic blood pressure to 220 mmhg with three episodes of generalized tonic clonic seizures . in intensive care unit ( icu ) , he was sedated with midazolam and propofol infusions and required upto two parenteral and four oral short acting antihypertensive drugs in the next 48 h under close monitoring . mri showed bilateral multifocal subcortical hyperintensities in t2-weighted imaging , with no diffusion restriction , in keeping with a diagnosis of pres [ figures 13 ] . he further received iv methylprednisolone 500 mg each for the next 2 days . on day 9 , he was discharged from the icu with five oral antihypertensive drugs including minoxidil and antiepileptic levetiracetam . serum creatinine had reached a nadir of 1.2 mg / dl on day 8 but increased to 1.6 mg / dl within a week . renal biopsy showed moderate to severe tubulitis with transplant glomerulitis , no hypertensive changes , and a negative c4d stain . he was treated as steroid - resistant acute cellular rejection with seven doses of antithymocyte globulin ( 2.5 mg / kg / day ) and serum creatinine normalized to 1.1 mg / dl . the tacrolimus trough was at 3.2 ng / ml and the dose was further increased . mri brain repeated 6 weeks later showed resolution of all abnormalities [ figure 4 ] . at 12 months after transplantation , he is doing well and has good graft function on three antihypertensive drugs . fluid - attenuated inversion recovery magnetic resonance image of the brain shows bilateral multifocal subcortical hyperintensities in the parietal lobe ( long white arrow ) with relative sparing of the left frontal lobe and also involvement of the deep white matter of the right internal capsule ( short white arrow ) and ganglionic region corresponding diffusion - weighted magnetic resonance image demonstrates lesions that are partially confluent and iso intense signals with no diffusion restriction ( white arrow ) those areas with increased signal intensities in fluid - attenuated inversion recovery   also have increased apparent diffusion coefficient values signifying vasogenic edema ( long and short white arrows ) magnetic resonance imaging brain shows that the previously noted bilateral multifocal non - enhancing , subcortical and deep white matter hyperintensities in the fluid - attenuated inversion recovery magnetic resonance image   have completely resolved pres was first described by hinchey et al . in 1996 as a clinico - radiological entity , characterized by typical neurological deficits , distinctive mri features , and usually a benign clinical course . most cases in literature have occurred after hematopoietic or liver transplants.[47 ] fifty cases of calcineurin inhibitor associated pres in transplant recipients reported in the literature were reviewed by singh et al . with only eight among renal transplant recipients . . looked at 77 consecutive renal transplant patients who presented with neurological symptoms and found mri findings of pres in 5% . these occurred most commonly within the first three months post - transplant , usually following immunosuppression given in the intravenous bolus form . contributing factors that led to pres in our patient are the young age , higher doses of corticosteroids , tacrolimus , and a prolonged period of uremia prior to transplant . in the article by wong et al . , most patients with pres had serum tacrolimus level in the therapeutic range and unlike our case , tacrolimus was restarted after a brief period of withdrawal . other studies have shown that there is no correlation with neurotoxicity and the trough levels of tacrolimus . a few case reports have shown high csf tacrolimus levels , when corresponding serum levels have been within therapeutic limits . , showed that polymorphisms in cyp3a5 , abcb1 , and mdr1 genes were linked to calcineurin - associated neurotoxicity . continuation of immunosuppression entails maintaining a balance between prevention of rejection and aggravation of neurotoxicity . in a setting of pres with no suspected rejection and low - risk transplant , reduction or even temporary interruption of tacrolimus though it is well recognized that blood levels of immunosuppressants do not correlate with the presence of pres , it still remains the only practical aid for guiding physicians . if the neurological recovery is delayed even after reduction , then temporary stoppage of calcineurin inhibitors may be necessary . pharmacogenomic studies may help in identifying susceptible patients , once widely available as a diagnostic test . a complete neurological recovery without cessation of tacrolimus has also been reported in two pediatric renal transplants by parvex et al . it is likely that our patient had a genetic polymorphism , though not formally tested , as he required high doses of tacrolimus ( 0.35 mg / kg / day ) to achieve the desired trough concentration in the serum . our report is the first to demonstrate that intensified immunosuppression , if clinically warranted can still be continued with close monitoring and control of blood pressures .
posterior reversible encephalopathy syndrome ( pres ) is an uncommon post - renal transplant complication . 
 we report a 16-year - old boy who had an acute cellular rejection immediate post - transplant and was given intravenous methylprednisolone along with an increase in tacrolimus dose . 
 he was diagnosed to have pres based on clinical and radiological features within 6 h of intensified immunosuppression . 
 this is an unusual case report of successfully managing pres with continuation of the intensified immunosuppression as warranted by the clinical situation , along with aggressive blood pressure control . 
 after 6 weeks , magnetic resonance imaging showed complete resolution of lesions . 
 he has good graft function and no residual neurological deficits while on small doses of three antihypertensives , 12 months after transplantation .