Comparing Estimated and Measured Glomerular Filtration Rate in Children with Posterior Urethral Valve.

Background: Posterior urethral valve (PUV) is obstructive uropathy that may lead to chronic kidney disease (CKD) and end-stage renal disease (ESRD) in children. Glomerular filtration rate (GFR) measurement remains the gold standard for renal function measurement. However, due to its less availability and cumbersome, it is not commonly used, and GFR is estimated utilizing various endogenous filtration markers. Objective: This study includes pediatric patients with PUV. We aimed to compare the measured GFR (mGFR) with various creatinine-based estimated GFR methods (eGFR). Materials and Methods: A single-center retrospective study included 62 treated cases of PUV, postvalve fulguration. The mGFR measured by 99mTc-diethylenetriaminepentaacetate in vitro method and compared with eight eGFR (Schwartz, Cockcroft-Gault [CG], Counahan-Barratt [CB], CKD Epidemiology Collaboration [CKD-EPI], full-age spectrum [FAS] age, FAS height (FAS Ht), Schwartz-Lyon [SL], and Ht independent). Patients were subdivided into different CKD grades and compared with various eGFR. Discussion: PUV is a common cause of CKD in children and needs special consideration as there is growth retardation associated with it. It decreases creatinine production and thus fallacies in eGFR measurement. There is a requisite to identify and closely monitor the subset of patients with baseline decreased renal function and therefore at risk of developing ESRD. Results: A total of 62 patients were included. Mean age and serum creatinine levels were 8.02 ± 5.53 years and 1.15 ± 0.95 mg/dl (range: 0.4-4.5), respectively. The mean mGFR was 61.6 ± 31.80 mL/min/1.73 m2 and a positive variable correlation was 0.46-0.77 between mGFR and eGFR. Based on mGFR, there were 14 (22.6%), 21 (33.8%), 13 (20.9%), 9 (14.5%), and 5 (8.1%) patients in Grades I-V, respectively. The correct classification of the CKD grades was noted in 25 (40.3%), 16 (25.8%), 32 (51.6%), 16 (25.8%), 25 (40.3%), 27 (43.5%), 26 (41.9%), and 28 (45.2%) patients by Schwartz, CG, CB, CKD-EPI, FAS age, FAS Ht, SL, and Ht-independent equation. The eGFR overestimates GFR at the lower level and underestimates at higher levels. Conclusion: Our results confirm the considerable limitations of various creatinine-based clearance methods for estimating actual GFR. The creatinine clearance-based eGFR should not replace the measurement of the GFR. An initial measure of the mGFR followed by serial follow-up with the eGFR equation may be done. The most accurate eGFR equations are CB for Grade II, SL or Ht independent for Grade III, FAS age for Grade IV, and SL for Grade V CKD.

Rib Plasmacytoma Presenting as Progressive Muscle Weakness.

We report the case of a young male who gradually developed a subacute demyelinating polyradiculoneuropathy. Routine examination and extensive biochemical investigations revealed demyelinating neuropathy, M-Band in electrophoresis. The patient referred for the whole-body 18F-fluorodeoxyglucose-positron emission tomography/computed tomography to look for skeletal and bone marrow lesions. The patient was found to have rib plasmacytoma. The case is rare because of infrequent association with the site, age, and symptoms.

Malakoplakia Presenting as a Mass in the Transplanted Kidney: A Malignancy Mimicker on PET/CT.

Malakoplakia is a rare inflammatory condition that can affect many organ systems, including the genitourinary tract. It is associated with impaired immune function. Isolated renal parenchymal involvement has been reported in very few cases. Urinary tract and digestive malakoplakia have been reported in transplant recipients, but the involvement of transplant itself is rare. Variable clinical manifestations and nonspecific radiological appearance make the diagnosis difficult. The differential diagnosis includes infective etiologies and malignancy. We report a case of renal allograft malakoplakia, mimicking as a malignancy on F-FDG PET/CT.

Idiopathic Hepatic and Splenic Uptake of 99mTc-Methylene Diphosphonate.

Tc-99m-methylene diphosphonate (MDP) bone scintigraphy is mainly directed toward identifying sites of altered skeletal metabolism and abnormal foci of calcium phosphate deposition due to various etiologies. One of the requirements of an ideal bone scintigraphy is little or no extraosseous uptake. Nonosseous uptake of MDP in the bone scintigraphy is an unusual finding. We report a case of carcinoma prostate referred for bone scan, where diffuse hepatic and splenic uptake has been seen on the bone scan. However, on a further repeat bone scan, there was no nonosseous uptake.

Lymphoscintigraphy In a Case of Recurrent Chylopericardium.

Chylopericardium is an uncommon and benign condition in which triglyceride-containing chylous fluid collects in the pericardial cavity at high concentrations. Usually, chylopericardium occurs due to congenital malformation of lymphatic vessels or secondary to any trauma, surgeries, neoplasms, etc. However, if exact aetiology cannot be identified, the condition is referred to as Idiopathic chylopericardium which is a very rare presentation in day-to-day clinical practice. General physical examination, routine blood investigations and various anatomical imaging modalities may give a clue in the diagnosis, however, diagnosis can be challenging as they have a variable presentation. Also, optimal treatment poses greater difficulty as it remains controversial in most cases. We report a 47-year-old gentleman who presented with recurrent chylous pericardial effusion with no history of trauma, thoracic surgeries, cardiac disease and neoplasm in the past. Lymphoscintigraphy confirmed the communication between the lymphatic trunk and the pericardial space. The patient was managed conservatively with pericardial drainage and the patient recovered is doing well at present.

Recurrent Renal Carcinoma with Solitary Intramedullary Spinal Cord Metastasis.

We report a case of an elderly male who has undergone right radical nephrectomy for renal cell carcinoma (RCC). Six months later, he presented with gradually progressive low backache and mild lower limb weakness. 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET-CT) was done that revealed a suspected area of mild metabolic activity in the spinal cords at the L1-L2 vertebral level. Magnetic resonance imaging revealed intramedullary spinal cord metastasis (ISCM). Solitary ICSM is a rare presentation of RCC on FDG PET-CT, and only a few case reports exist in the literature. This case highlights that adequate clinical history and careful examination of the PET images may reveal it.