Introduction:
BARDET-BIEDL SYNDROME (BBS) IS A RARE GENETIC SYNDROME CAUSING RENAL INVOLVEMENT IN THE FORM OF CONGENITAL MALFORMATIONS AND/OR RENAL PARENCHYMAL DISEASE, WHICH ULTIMATELY LEADS TO CHRONIC KIDNEY DISEASE (CKD), REQUIRING RENAL TRANSPLANTATION AND POST TRANSPLANTATION CARE IS AS PER THE STANDARD PROTOCOL WITH TRIPLE IMMUNOSUPPRESSION. TACROLIMUS IS AN INTEGRAL PART OF THIS IMMUNOSUPPRESSION REGIMEN AND IT IS KNOWN TO CAUSE SOME SHORT AND LONG TERM SIDE EFFECTS. NEUROLOGICAL ADVERSE EFFECTS ARE RARE AND MILD, HOWEVER SERIOUS ADVERSE EFFECTS LIKE SEIZURES ARE EXTREMELY RARE.
Methods:
A 15 YEAR FEMALE PATIENT OF BARDET-BIEDL SYNDROME WITH SEIZURES IN EARLY POST RENAL TRANSPLANT PERIOD DUE TO TACROLIMUS ASSOCIATED POSTERIOR REVERSIBLE LEUKOENCEPHALOPATHY SYNDROME (PRES).
Results:
WE REPORT A CASE OF A 15-YEAR-OLD FEMALE BORN OF A NON-CONSANGUINEOUS MARRIAGE, PRESENTED WITH CLINICAL FEATURES OF RETINAL PIGMENT EPITHELIUM [RPE] ATROPHY CHANGES, DEVELOPMENTAL DELAY, RENAL DYSFUNCTION WITH PRIMARY AMENORRHEA, HYPERTENSION, HEARING DEFECT, SHORT NECK, POSTAXIAL POLYDACTYLY IN ALL FOUR LIMBS, SPARSE PUBIC AND AXILLARY HAIR, SANDAL GAP, HYPOPLASTIC UTERUS, HYPERECHOGENIC KIDNEYS, HYPOGONADISM AND OBESITY. SHE WAS DIAGNOSED AS A CASE OF BARDET-BIEDL SYNDROME WITH CKD, BASED ON CLINICAL PRESENTATION AND GENOME SEQUENCING WITH HOMOZYGOUS 6 BASE PAIR DELETION IN EXON 15 OF THE BBS7 GENE. SHE WAS ON MAINTENANCE HAEMODIALYSIS FOR 1 YEAR WITH NO HISTORY OF SEIZURES OR NEUROLOGICAL DEFICITS IN PAST. HER RENAL TRANSPLANTATION WAS DONE WITH MOTHER AS THE DONOR. SHE HAD TWO EPISODES OF TONIC-CLONIC SEIZURES ON DAY TWO POST-TRANSPLANT. BIOCHEMICAL INVESTIGATIONS WERE GROSSLY NORMAL WITH NO ELECTROLYTE ABNORMALITIES ALONG WITH A BLOOD UREA NITROGEN OF 28 AND SERUM CREATININE OF 1.1 MG/DL. HER TACROLIMUS TROUGH LEVELS WERE 9.76 NG/ML. MRI BRAIN SHOWED ILL-DEFINED T2W/FLAIR CORTICAL AND SUBCORTICAL HYPERINTENSITIES WITH MAINTAINED GREY WHITE MATTER DIFFERENTIATION LOCATED PREDOMINANTLY IN THE BILATERAL PARIETAL, OCCIPITAL LOBES, RIGHT BASAL GANGLIA AND SUBCORTICAL WHITE MATTER. EEG REVEALED MILD BACKGROUND SLOWING CONSISTENT WITH ENCEPHALOPATHY. ALTHOUGH PRES SECONDARY TO TACROLIMUS WAS A DIFFERENTIAL DIAGNOSIS, GIVEN UNUSUAL TIME COURSE, AND NORMAL TROUGH LEVELS, DRUG WAS CONTINUED. ONE DAY LATER PATIENT ALSO DEVELOPED HORIZONTAL GAZE PALSY, DIMINISHED VISION IN BOTH EYES ALONG WITH COMPLAINT OF SEVERE NAUSEA. AT THIS STAGE, THE PATIENT'S TACROLIMUS WAS DISCONTINUED AND SHE WAS INITIATED ON CYCLOSPORINE. MRI BRAIN WAS REPEATED THREE DAYS LATER WHICH SHOWED REDUCTION IN THE VASOGENIC EDEMA IN PREVIOUS AFFECTED AREAS OF BRAIN. NO RECURRENT SEIZURES OCCURRED IN 10 DAYS OF INTRA-HOSPITAL AND TILL DATE FOLLOW-UP PERIOD.
Conclusions:
TACROLIMUS INDUCED PRES CAN OCCUR IN EARLY POST RENAL TRANSPLANT PERIOD EVEN IN SUB-THERAPEUTIC CONCENTRATION. THE CASE EMPHASIZES THE CRITICAL BALANCE BETWEEN ADEQUATE IMMUNOSUPPRESSION AND THE RISK OF SEVERE NEUROLOGICAL ADVERSE EFFECTS. SECONDLY A CLINICIAN SHOULD ALWAYS HAVE A KEEN VISION TO EVALUATE AND DIAGNOSE BBS IN PATIENTS WITH RENAL DISEASE, CHARACTERISTIC PHENOTYPE AND OTHER SYNDROMIC FEATURES.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.