Hyperchloremic Metabolic Acidosis with Hyperglycemic Hyperosmolar Syndrome after Robot-Assisted Radical Cystoprostatectomy with Ileal Conduit Urinary Diversion: A Case Report

Hyperchloremic metabolic acidosis can be a problem in urinary diversion using the ileum. A 73-year-old Japanese male was hospitalized in emergency due to anorexia and malaise 3 weeks after being discharged from the hospital after getting robot-assisted radical cystoprostatectomy and intracorporeal ileal conduit urinary diversion. The blood analysis revealed metabolic acidosis, elevated chloride ions, and marked hyperglycemia: he was diagnosed with hyperchloremic metabolic acidosis and hyperglycemic hyperosmolar syndrome. We started administering insulin and large amounts of fluid replacement; besides, we inserted a large-diameter open tip catheter into the ileal conduit in hopes of inhibiting urine reabsorption in the intestinal mucosa. His general condition gradually improved, and he was discharged 10 days after his hospitalization.

Case Report: Uroenteric Fistula in a Pediatric-en-bloc Kidney Transplant Manifests as Deceptive Watery Diarrhea and Normal Anion Gap Acidosis

Introduction: The diagnosis of a post–surgical uroenteric fistula can be challenging and may be delayed for months after symptoms begin. A normal anion gap metabolic acidosis has been reported in up to 100% of patients after ureterosigmoidostomy, and bladder substitution using small bowel and/or colonic segments. Here, we describe a rare case of a pediatric patient who developed a uroenteric fistula from the transplant ureters into the small bowel, after an en-bloc kidney transplantation resulting in profound acidosis and deceptive watery diarrhea.Case Presentation: The patient is an 8-year-old girl with end stage kidney disease (ESKD) secondary to focal segmental glomerulosclerosis. Through a right retroperitoneal approach, she underwent a right native nephrectomy and a pediatric deceased donor en-bloc kidney transplant including two separate ureters. One month later, she had a renal allograft biopsy for suspected rejection. During the week after the biopsy, she experienced abdominal pain followed by watery diarrhea and metabolic acidosis requiring continuous bicarbonate/acetate infusions. An extensive gastro-intestinal evaluation for the cause of the diarrhea including endoscopy was inconclusive. The urine output decreased to <500 ml daily; although, the kidney function remained normal. After 2 weeks of unexplained watery diarrhea a magnetic resonance urogram with contrast was performed which demonstrated extravasation of urine from both ureters with fistulization into the small bowel. She underwent corrective surgery which identified the fistulous tract, which was resected and both ureters were re-implanted. The diarrhea and acidosis resolved, and she has maintained normal renal allograft function for over 1 year.Conclusion: An important aspect in the early diagnosis of a uroenteric fistula is the sudden onset of severe hyperchloremic metabolic acidosis that results when urine is diverted into the intestinal tract. The mechanism is similar to that described in cases of urinary diversions and/or bladder augmentation using the intestine. Important diagnostic tools are the measurements of solute excretion and pH in the urine as compared to the “watery diarrhea” or bowel output.Summary: We describe a case of a uroenteric fistula in a pediatric-en-bloc kidney transplant patient that went undiagnosed for almost 3 weeks due to the deceptive nature of the watery diarrhea which was actually urine. A uroenteric fistula should be considered in the differential diagnosis of diarrhea and hyperchloremic metabolic acidosis as a complication of kidney transplant. The simultaneous comparison of stool and urine pH and solute excretions may lead to the diagnosis, appropriate imaging and surgical intervention.

Hyperchloremic metabolic acidosis during bipolar transurethral resection of the prostate: a report of two cases

Compared with monopolar transurethral resection of the prostate (TURP), which requires electrolyte-free irrigation fluid, normal saline can be used as the irrigation solution in bipolar and laser TURP. The risk of TURP syndrome and severe electrolyte disturbance is minimized when normal saline is used as the irrigation fluid. However, the use of isotonic saline also causes acid-base imbalance and electrolyte disturbance. We experienced two patients who developed hyperchloremic metabolic acidosis during bipolar TURP. After proper intervention, hemodynamic instability resolved, and laboratory test results normalized. Anesthesiologists must pay attention to acid-base and electrolyte status when rapid absorption of excessive isotonic solution is suspected, even during bipolar and laser TURP, which use normal saline as the irrigation fluid.

Biallelic loss-of-function variants in KCNJ16 presenting with hypokalemic metabolic acidosis

KCNJ16 encodes Kir5.1 and acts in combination with Kir4.1, encoded by KCNJ10, to form an inwardly rectifying K+ channel expressed at the basolateral membrane of epithelial cells in the distal nephron. This Kir4.1/Kir5.1 channel is critical for controlling basolateral membrane potential and K+ recycling, the latter coupled to Na-K-ATPase activity, which determines renal Na+ handling. Previous work has shown that Kcnj16−/− mice and SSKcnj16−/− rats demonstrate hypokalemic, hyperchloremic metabolic acidosis. Here, we present the first report of a patient identified to have biallelic loss-of-function variants in KCNJ16 by whole exome sequencing who presented with chronic metabolic acidosis with exacerbations triggered by minor infections.

Case Report: Irreversible Watery Diarrhea, Severe Metabolic Acidosis, Hypokalemia and Achloridria Syndrome Related to Vasoactive Intestinal Peptide Secreting Malignant Pheochromocytoma

BackgroundPheochromocytoma (PHEO) clinical manifestations generally mirror excessive catecholamines secretion; rarely the clinical picture may reflect secretion of other hormones. Watery diarrhea, hypokalemia and achlorhydria (WDHA) is a rare syndrome related to excessive secretion of vasoactive intestinal peptide (VIP).Clinical CaseA 73-year-old hypotensive man affected by adrenal PHEO presented with weight loss and watery diarrhea associated with hypokalemia, hyperchloremic metabolic acidosis (anion gap 15 mmol/l) and a negative urinary anion gap. Abdominal computed tomography scan showed a right adrenal PHEO, 8.1 cm in maximum diameter, with tracer uptake on 68GaDOTA-octreotate positron emission tomography. Metastasis in lumbar region and lung were present. Both chromogranin A and VIP levels were high (more than10 times the normal value) with slightly elevated urine normetanephrine and metanephrine excretion. Right adrenalectomy was performed and a somatostatin analogue therapy with lanreotide started. Immunostaining showed chromogranin A and VIP co-expression, with weak somatostatin-receptor-2A positivity. In two months, patient clinical conditions deteriorated with severe WDHA and multiple liver and lung metastasis. Metabolic acidosis and hypokalemia worsened, leading to hemodynamic shock and exitus.ConclusionsA rare case of WDHA syndrome caused by malignant VIP-secreting PHEO was diagnosed. High levels of circulating VIP were responsible of the rapidly evolving clinical picture with massive dehydration and weight loss along with severe hyperchloremic metabolic acidosis and hypokalemia due to the profuse untreatable diarrhea. The rescue treatment with lanreotide was unsuccessful because of the paucity of somatostatin-receptor-2A on VIP-secreting PHEO chromaffin cells.

Clinical approach to renal tubular acidosis in children

Renal tubular acidosis (RTA) is a common inherited tubulopathy in children. Proximal RTA, usually secondary to a systemic metabolic disease, is characterized by a generalized dysfunction of the proximal tubule resulting in Fanconi syndrome. Distal RTA occurs due to mutation in the transporters of the distal tubule resulting in acidification defects. Hyperchloremic metabolic acidosis with normal anion gap is the characteristic feature of RTA. In addition to supportive therapy, specific treatment for the underlying etiology and regular monitoring of growth and laboratory parameters are of utmost importance.

Chloremia and Fluid Therapy – A Systematic Review

Background: Crystalloid solutions are one of the most widely used remedies in the field. While generally used in medicine for almost 190 years, studies focused largely on their safety have only been published since the new millennium. The most widely used solution, normal saline, is most often referred to in this context. Its excessive administration results in hyperchloremic metabolic acidosis with other consequences, including higher mortality rates. Current balanced solutions are safer in this respect and are designed to have a composition close to that of blood plasma.Methods: Original papers and review articles eligible for developing the present paper were identified by searching online in the electronic MEDLINE database. The key words searched for included hyperchloremia, hypochloremia and compound words containing the word “chloride”, infusion therapy, metabolic acidosis, renal failure, and review.Results: A total of 21,758 papers published before 31 May 2020 were identified; of this number, 630 duplicates were removed from the list. Upon excluding articles based on their title or abstract, 1850 papers were screened, of which 63 full-text articles were assessed.Conclusions: According to the latest medical concepts, dyschloremia (both hyperchloremia and hypochloremia) is a factor indisputably having a negative effect on selected variables of clinical outcome. As infusion therapy can significantly impact chlorine homeostasis of the body, the choice of infusion solutions should always take into account the potentially adverse impact of chlorine content on chloremia and organ function.

P0002A NEW INSIGHT INTO THE MECHANISM OF HYPERCHLOREMIC METABOLIC ACIDOSIS IN KIDNEY TRANSPLANT RECIPIENTS: INCREASED POSTGLOMERULAR PERITUBULAR BLOOD FLOW IS A KEY CONDITION FOR THE DEVELOPEMENT OF CALCINEURIN INHIBITOR-INDUCED RENAL TUBULAR ACIDOSIS

Background and Aims Hyperchloremic metabolic acidosis (HCMA) due to renal tubular acidosis is a common complication in kidney transplant recipients(KTR). Potential renal dysfunction, rejection, ischemia, persistent hyperparathyroidism, calcineurin inhibitors (CNIs), etc. have been identified as causes but have not been fully proven, and whether HCMA is a determinant of poor graft prognosis in KTR is still controversial. The purpose of this study is to elucidate the actual mechanism of HCMA in KTR. Method HCMA was defined as follows: i) simple strong ion difference (SID) Na-CL, which is the most dominant metabolic factor in physicochemical approach for acid-base balance, is 34 or less, or â…±) the alkalizing drugs have been started after the KT to correct HCMA. And all the cases of having diarrhea from mycophenolate mofetil(MMF), and gastroenterocolitis from cytomegalovirus infection were excluded. The study group consisted of 47 KTRs who underwent living-kidney transplantation(KT) at our hospital as well as a control group of 43 of the matched donors. Among them, a total of 26 KTRs received the renal hemodynamic studies which were based on urinary clearance of inulin and para-aminohippuric acid 1year after KT. 1) The incidence of HCMA in KTR at 3 months(3m) and 1 year(1y) after KT were examined. 2) To elucidate factors related to HCMA in KTR at 1y, we comprehensively examined factors and compared HCMA groups with non-HCMA groups; donor and recipient background (gender, age, body size), immunological factors, information on transplant surgery, salt and protein intake, effective buffering factors for extracellular body fluids such as albumin and hemoglobin, serum calcium and phosphate concentrations and their ratios, administration of renin-angiotensin system inhibitors and diuretics,Tac trough level and Banff score of each histopathological lesion in 1y biopsy. As for the 26 KTRs who received the renal hemodynamic studies, glomerular filtration rate (GFR), renal plasma flow (RPF), filtration fraction(FF) (GFR/RPF) and pre-/post-glomerular vascular resistance (pre-/postVR) calculated from the Gomez' equations were also analyzed. Results 1) The incidence of HCMA in the KTR at 3m was 51% (24/47), which was much higher than the 6.9% (3/43) in those donors (p<0.001), and the range of odds ratios (vs donor) adjusted by the background factors (age,gender, estimated GFR, albumin and hemoglobin) was 6.7-15.7 (p=0.0001-0.001). The incidence of HCMA in KTR at 1y decreased to 34%. 2)The univariate analysis of HCMA in KTR at 1y compared with non-HCMA showed an increase in RPF (p= 0.016), a decrease in post-VR (p= 0.003), and a decrease in FF (p= 0.0001), suggesting an increase in post-glomerular peritubular blood flow. In addition, the aah lesion score, an indicator of CNI vasculopathy, was also significantly higher in the HCMA (p = 0.015). There was no difference in Tac trough levels between HCMA and nonHCMA, and no independent factors were found by multivariate analysis. All cases with HCMA were classified into low post-VR (Fig.1). Furthermore, in low post-VR alone (n= 15), the Tac trough level at 1y was significantly higher in the HCMA (p= 0.002) (Fig.2). Conclusion In kidney transplant recipients, increased post-glomerular peritubular blood flow is a key condition for the development of CNI-induced renal tubular acidosis. The presence of HCMA suggests that it is probably not a serious condition, but rather a desirable hemodynamic state, however, more attention should be paid not to elevate CNI concentration levels in such conditions.

A case of Fanconi syndrome as a complication of treatment with a checkpoint inhibitor in a patient with hepatocellular carcinoma

Introduction: Immune checkpoint inhibitors (CPIs) represent novel new cancer immunotherapy agents. The use of nivolumab has been linked with immune mediated acute interstitial nephritis (AIN). Case Presentation: We present the case of a patients with recurrent hepatocellular carcinoma who developed severe Fanconi syndrome, as evidenced by hyperchloremic metabolic acidosis, hypokalemia, hypophosphatemia, glucosuria, aminoaciduria, 8 months after initiating treatment with nivolumab, without any evidence of acute renal insufficiency. Conclusion: Clinicians need to be aware of the renal side effects of new novel cancer immunotherapy agents, such as, immune CPIs