Background - Chronic kidney disease with unknown aetiology (CKDu) is a progressing disease which is affecting many Sri Lankans’ yearly, this disease is slow progressive, irreversible and asymptomatic disease. Patients suffering from CKDu over the past two decades have been evaluated using the estimated glomerular filtration rate (e-GFR). This is the standard test performed under WHO guidelines to investigate and grade the CKDu, and this creatinine clearance is measured in this in order to grade the patient. Backache has been a common symptom presented in most of the chronic kidney disease patients (CKD), patients with CKDu are liable to get backache due to the renal failure that takes place (Jayathilake et al., 2013; Redmon et al., 2016). Objective – To detect a correlation between serum creatinine values and level of backache presented in the patient. Method -Using an interview based questionnaire to assess patients’ body condition and the degree of backache is assessed, 59 patients were part of the study for a period of five months and had an average age of 60.3 years. The questionnaire answers are scaled into four main types of backache from the least to the most painful based on the pain scale adapted from Kapkia. Serum creatinine is measured using an automated analyzer which is measured using Jaffe’s reaction. Using Pearson R correlation, the relationship was determined between serum creatinine and backache (Kafkia et al., 2011). Results – The results were obtained for 58 patients (n=58), where the mean backache score was 2.30 and mean serum creatinine value 2.77. The Pearson R value obtained was 0.01 which is indicating almost no relationship between backache and serum creatinine. Patients with stage 3 kidney disease (n=14) had an average E-GFR of 38.0, stage 4 (n=38) with 22.3 and stage 5 (n=6) with 14.0. Conclusion – Backache can be used an indicator of CKDu since it is presented in most patients’ suffering from the disease but unable to be used to determine the stage of CKDu suffered by the patient due to the external causes that leads to backache. Several predisposing factors such as temperature, water source and agricultural activity can influence the backache.

Kinetic estimation of glomerular filtration rate (KeGFR) proved its utility in predicting acute kidney injury (AKI) in both adults and children. Our objective is to assess the clinical utility of KeGFR in predicting AKI severity and progression to acute kidney disease (AKD) in patients already diagnosed with AKI and to examine major adverse kidney events at 30 days (MAKE30). We retrospectively calculated the KeGFR in the first 24 hours of identified AKI (KeGFR1) and in the 24 hours prior to AKD (KeGFR2) in all admitted children under 18 years old. The cohort consisted of 803 patients with AKI. We proposed a new classification of KeGFR stages, from 1 to 5, and assessed the predictive value of KeGFR stages for AKD development and MAKE30. AKI severity was associated with lower KeGFRs. KeGFR1 and KeGFR2 predicted AKD with AUC values between 0.777 and 0.841 respectively, p<0.001. KeGFR2 had the best performance in predicting MAKE30 (AUC of 0.819) with a sensitivity of 66.67% and specificity 87.7%. KeGFR1 stage 3, 4 and 5 increased the risk of AKD by 3.07, 6.56 and 28.07 times respectively while KeGFR2 stage 2, 3, 4 and 5 increased the risk of AKD 2.79, 3.58, 32.75 and 80.14 times fold. Stage 5 KeGFR1 and KeGFR2 stages 3, 4 and 5 increased the risk of MAKE30 by 7.77, 4.23. 5.89 and 69.42 times in the adjusted models. KeGFR proved to be a useful tool in AKI settings. KeGFR dynamics can predict AKI severity, duration and outcomes.

Thalassemia is one of the most prevalent genetic disorders worldwide which has been previously found to have an association with several physiological and organ complications. Several studies found both its positive and inverse correlation with glomerular filtration rate (GFR). Therefore, in this meta-analysis, we tried to assess the accurate correlation of thalassemia with GFR. We searched in Google Scholar, PubMed, and ScienceDirect, and from the initial 96 articles we finally could include 15 studies. The quality and publication bias assessment confirmed that all the studies were of high to moderate quality with no publication bias. The main outcome of the mean difference (MD) was -6.45, 95%CI: -18.50, 5.60 (P<0.00001), which indicated a negative correlation of GFR with thalassemia. The sensitivity analyses found one study as a slight outlier and reanalyzing the data excluding that study MD was achieved as -13.90, 95%CI: -24.22, -3.59 (P<0.00001) which even strongly supports our main outcome. Our result determined that the GFR is generally higher in healthy people as compared to thalassemia patients.

Cadmium (Cd) is a pervasive, toxic environmental pollutant that preferentially accumulates in tubular epithelium of the kidney. Current evidence suggests that the cumulative burden of Cd here leads to progress loss of the glomerular filtration rate (GFR). In this study, we have quantified changes in estimated GFR (eGFR) and albumin excretion (Ealb) in according to levels of blood Cd ([Cd]b) and excretion of Cd (ECd) after adjustment for confounders. ECd and Ealb were normalized to creatinine clearance (Ccr) as ECd/Ccr and Ealb/Ccr. Among 482 residents of Cd-polluted and non-polluted regions of Thailand, 8.1% had low eGFR and 16.9% had albuminuria, (Ealb/Ccr)×100 ≥ 20 mg/L filtrate. In the low Cd burden group, (ECd/Ccr) ×100 &lt; 1.44 µg/L filtrate, eGFR did not correlate with ECd/Ccr (β = 0.007), while an inverse association with ECd/Ccr was found in the medium (β =−0.230) and high-burden groups (β =−0.349). Prevalence odds ratios (POR) for low eGFR were increased in the medium (POR 8.26) and high Cd burden groups (POR 3.64). Also, eGFR explained a significant proportion of Ealb/Ccr variation among those with middle (η2 0.093) and high [Cd]b tertiles (η2 0.132), but did not with low tertile (η2 0.001). With adjustment of eGFR, age and BMI, POR values for albuminuria were increased in the middle (POR 2.36) and high [Cd]b tertiles (POR 2.74) and those with diabetes (POR 6.02) and hypertension (2.05). These data argue that ECd/Ccr of 1.44 µg/L filtrate (0.01−0.02 µg/g creatinine) could determine a Cd threshold level from which protective exposure guidelines should be formulated.

Excretion of β2-microglobulin (β2M) above 300 µg/g creatinine, termed tubulopathy, was regarded as the critical effect of chronic exposure to the metal pollutant cadmium (Cd). However, current evidence suggests that Cd may induce nephron atrophy, resulting in a reduction in the estimated glomerular filtration rate (eGFR) below 60 mL/min/1.73 m2. Herein, these pathologies were investigated in relation to Cd exposure, smoking, diabetes and hypertension. Data were from 448 residents of Cd-polluted and non-polluted regions of Thailand. The body burden of Cd, indicated by the mean Cd excretion (ECd) normalized to creatinine clearance (Ccr) as (ECd/Ccr) ×100 in women and men did not differ (3.21 vs. 3.12 µg/L filtrate). The prevalence odds ratio (POR) for tubulopathy and a reduced eGFR were increased by 1.9-fold and 3.2-fold for every 10-fold rise in Cd body burden. In women only, a dose-effect relationship was seen between β2M excretion (Eβ2M/Ccr) and ECd/Ccr (F = 3.431, η2 0.021). In men, Eβ2M/Ccr was associated with diabetes (β = 0.279). In both genders, eGFR was inversely associated with Eβ2M/Ccr. The respective covariate- adjusted mean eGFR values were 16.5 and 12.3 mL/min/1.73 m2 lower in women and men who had severe tubulopathy; (Eβ2M/Ccr) ×100 ≥ 1000 µg/L filtrate. These findings indicate that women were particularly susceptible to the nephrotoxicity of Cd, and that the increment of Eβ2M/Ccr could be attributable mostly to Cd-induced impairment in tubular reabsorption of the protein together with Cd-induced nephron loss, evident from an inverse relationship between Eβ2M/Ccr and the eGFR.

In healthy adult brain, glial cell line-derived neurotrophic factor (GDNF) is exclusively expressed by neurons and in some instances, it has furthermore been shown to derive from a single neuronal subpopulation. Secreted GDNF acts in a paracrine fashion by forming a complex with GDNF family receptor α1 (GFRα1) which is mainly expressed by neurons and can act in cis as a membrane-bound or in trans as a soluble factor. The GDNF/GFRα1 complex signals through interaction with RET (“rearranged during transfection”) or with a lower affinity with neural cell adhesion molecule (NCAM). GDNF can also signal independently from GFRα1 via interaction with syndecan-3. RET being expressed by neurons involved in several pathways: nigro-striatal dopaminergic neurons, motor neurons, enteric neurons, sensory neurons, etc. could be the main determinant of the specificity of GDNF pro-survival effect. In injured brain, de novo expression of GDNF occurs in glial cells. Neuroinflammation has been reported to induce GDNF expression in activated astrocytes and microglia, infiltrating macrophages, nestin-positive neural stem cells and neuron/glia (NG2) progenitors. This disease-related GDNF overexpression can be either beneficial or detrimental depending on the localization in the brain and the level and duration of glial cells activation. Some reports also describe upregulation of RET and GFRα1 in glial cells, suggesting that GDNF could modulate neuroinflammation.

Cadmium (Cd) is a metal with no nutritional or physiological value, but is found in most people because it is a contaminant in nearly all food types. The intestinal absorption rate determines the body burden of Cd because humans lack a physiologic mechanism for excretion of the metal. Most acquired Cd accumulates in the kidneys, in which the Cd content increases through age 50 but falls thereafter. The decline from maximal kidney content is probably due to release of Cd from injured tubular cells into urine and replacement of destroyed nephrons by scar tissue. Chronic kidney disease is diagnosed when the estimated glomerular filtration rate (eGFR) falls below 60 mL/min/1.73 m2, or when albuminuria is present. Albuminuria is defined as an albumin-to-creatinine ratio ≥ 30 mg/g creatinine in women or ≥ 20 mg/g creatinine in men that persists for at least 3 months. Generally, Cd-induced reductions in eGFR are not reversible, and Cd nephropathy may progress to end-stage kidney disease. There is no evidence that elimination of current environmental exposure can reverse Cd nephropathy, and no theoretical reason to believe that such a reversal is possible. This review provides an update of knowledge concerning CKD in population environmentally exposed to Cd. Special attention is devoted to mechanisms of Cd-induced albuminuria concurrently with eGFR reductions, and the difficult challenge of exposure guidelines sufficient to eliminate the risk of Cd-induced CKD is addressed.

Renal artery thrombosis is a sporadic serious clinical condition which potentially cause renal infarction. Diagnosis of renal infarction can be delayed or missed due to non specific clinical presentation and overlapping appearance of medical and surgical phenomena. Early diagnosis supported by biochemical and radiological findings while appropriate management potentially improve morbidity and mortality. Persistent abdominal or flank pain with raised LDH and proteinuria on background of thromboembolism risk factors supports the diagnosis. Despite the rarity of the disease rapid identification with prompt medical or endovascular intervention could prevent irreversible renal parenchymal damage.