Pediatr Nephrol
DOI 10.1007/s00467-014-2786-7
CLINICAL QUIZ
Mass lesions in the transplanted kidney: Questions
Kwanchai Pirojsakul & Jerry Powell & Anita Sengupta &
Dev Desai & Mouin Seikaly
Received: 3 February 2014 / Revised: 4 February 2014 / Accepted: 7 February 2014
# IPNA 2014
Keywords Mass lesions . Transplanted kidney
Case summary
A 14 year-old female patient presented with fever, nausea, and
dysuria. Her medical history included spina bifida and neuro-
genic bladder. She was on intermittent catheterization through
her appendicovesicostomy. Over time, she developed reflux
nephropathy and progressed to end-stage renal disease
(ESRD), at which point she was started on peritoneal dialysis.
She had bilateral nephrectomy and received a deceased-donor
kidney transplant 1 year before this presentation. Her mainte-
nance immunosuppression included prednisolone, mycophe- Fig. 1 Two complex, solid, and cystic mass lesions with internal vascu-
larity at the upper and lower poles of the transplanted kidney
nolate mofetil, and tacrolimus. She developed two episodes of
Escherichia coli urinary tract infection 1 and 4 months after
transplant. Vital signs were as follows: blood pressure (BP)
118/65 mmHg, pulse rate (PR) 110/min, respiratory rate (RR)
18/min, and temperature (T) 38.5 C. Physical examination
was unremarkable except for mild renal allograft tenderness.
Laboratory investigations were as follows: white blood cell
count (WBC) 2,300/ul [polymorphonuclear leukocytes
(PMN) 63 %, lymph 32 %, mononuclear leukocytes (mono)
3 %], hemoglobin (Hb) 7.6 g/dl, platelet 284,000/l, blood
urea nitrogen (BUN) 12 mg/dl, serum creatinine (sCr) 1.3 mg/
dl (baseline 0.9 mg/dl), and C-reactive protein (CRP) 13.8 mg/
The answers to these questions can be found at http://dx.doi.org/10.1007/
s00467-014-2788-5.
K. Pirojsakul : J. Powell : A. Sengupta : D. Desai : M. Seikaly (*)
Department of Pediatrics, University of Texas Southwestern Medical
Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA
e-mail: Mouin.Seikaly@utsouthwestern.edu
Fig. 2 Three large, complex masses with solid and cystic components in
K. Pirojsakul : J. Powell : A. Sengupta : D. Desai : M. Seikaly the transplanted kidney, with the largest lesion measuring up to 5.6 cm in
Childrens Medical Center, Dallas, TX, USA the inferior pole
Pediatr Nephrol
Fig. 4 Hematoxylin and eosin staining (630) of mass lesions in the
Fig. 3 Hematoxylin and eosin staining (100) of mass lesions in the
renal allograft
renal allograft
dl (normal range 01 mg/dl)]. Urinalysis showed ten WBCs/ ology for tissue diagnosis. Pathology finding are shown in
high power field (HPF) and positive for nitrite. Renal sono- Figs. 3 and 4.
gram of the allograft was performed and showed two com-
plex, solid, and cystic mass lesions with internal vascularity at
the upper and lower poles of the transplanted kidney (Fig. 1). Questions
Magnetic resonance imaging (MRI) revealed three large, com-
plex masses with solid and cystic components in the 1. What is the differential diagnosis of the mass lesions seen
transplanted kidney, with the largest measuring up to 5.6 cm in the renal allograft?
in the inferior pole (Fig. 2). There were additional smaller, 2. Please describe histopathologic findings in Figs. 3 and 4.
oval, subcentimeter masses scattered throughout the kidney. 3. What is the most likely final diagnosis and therapy for this
Renal allograft biopsy was performed by interventional radi- condition?
