Urinary Flashcards
What is FGF-23?
a phophotonin that works in concert with a-klotho to regulate phosphate when phosphate is increased.
Where is FGF-25 secreted from?
Why?
Osteoblasts and osteoclasts.
Response to high filtered load of phosphate in the nephron (secondary to increased phosphate absorption from the GIT)
What is the role of FGF-25?
Binds FGF-1 receptror and a-Klotho to down regular 2 Na-Phos transporters in the prox tubule (NPT2a and NPT2c) => reduced reabsorption of filtered phosphate => increased urinary excretion of phosphate . (dependant on GFR and plasma phos conc)
- inhib phosphate absorption from GIT via inhim conversion of 25-OHcholecalciferol to calcitriol via effections on both the calcitrol synthesising (CYP27B1) and catabolising (CYP24A1) enx.
- inhib phosphate absorption from both via inhib PTH secretion.
in regards to renal disease, when does increases in FGF-25 start to occur?
Early renal disease prior to onset of azotaemia (Stage 1) and increases proportionately with the stage of CKD (consistent with reduced GFR given it is renally excreted).
However can be excessively increased compared to plasma phosphate targets for given stage.
What is FGF-25 a marker for in cats?
- the stage of feline CKD
- predictive of progression of the development of azoaemia
- phsophate overload and potentially thus whether phosphate restriction may be beneficial
- all cause mortality.
Is FGF-25 affected by dietary phosphate restriction?
yes - causes reduction.
What is Klotho?
a paracrine and endocrine, transmembrane protein.
Where is it expressed and in what forms?
a-Klotho: transmembrane protein
- distal renal tubules
- PTH gland
- Choroid plexus
- Vascular tissues.
Soluble Klotho: - body fluids inc CSF, blood and urine from the shedding of membrane Klotho
B-Klotho: fibroblast growth factor for bile acid synthesis and lipit metabolism.
- liver
- pancreas
- adipose tissue
What does Klotho do?
- A-Klotho = Obligate co-receptor for FGF-23 => reduce circ phosphorus
- inactivate Na-P cotransporters type 2 (NaPi-2) = > inhib renal phos reabsorption
- reduce 1a-hydroxylase and increase 24-hydroxylase => reduced calcitriol - Soluble Klotho:
- activates TRPV5 and TRPV6 calcium channels in distal tubles => increased renal calcium reabsorption
- down reg NaPi-3 cotransporters to mediate phosphate uptake
- Activates ROMK1 K+ channels => increased K+ excretion in kidneys
- up reg NO production
- Increase Na+’K+ATPase in kidney , PTH gland and choroid plexus => Na and Ca+ homeostasis.
- Inhib insulin and IGF1 => insulin resistance
What decreases Klotho expression?
- ATII
- Oxidative stress/inflam cytokines (TNF-a)
- CKD
- Immune med glomerulopathy
in CKD:
- hyperphosphateamia
- hyper calcaemia
- reduced calcitriol
- inflam cytokines
- dyspilidaemia
- activated RAAS
What increases Klotho?
Age - younger = higher
- healthy = higher
- Calcitrol
- ARBs
What is the prevalence of hypernatraemia in dogs and cats?
does this affect prognosis?
Dogs - 5.7%
Cats 8%
hypernatraemia assocaited with 20-28% risk of death with higher Na associaed with higher case fataily.
Ueda JVIM 2015
What is hyperchloremic metabolic acidosis?
What are the causes?
- decrease pH
- decrease HCo3- or base excess
- increase chloride
- decreased in strong ion difference
- normal anion gap
Causes:
- Excessive sodium loss ralative to chrloide
- excessive gain of chloride relative to sodium (0.9% NaCl, salt poisoning, TPN with AA containing fluids)
- Chloride retention (early CKD, hypoA, spironolactone, corection of DKA, RTA)
Funes VCNA 2017
What are the causes of hyperkalaemia?
only really if kidneys not working to excrete.
- Extra-renal
- increased intake (only wiht concurrent issues kidney/adrenal/drugs)
- GI disease (trichuris, salmonela, perf duodenal ulcer)
- Chylothorax, plerual or peritoenal effusions (thrid space fluid loss) - Translocation from intracellular to extracellular fluid
- DKA/insulin deficiency
- Massive sittue break down/Tumour lysis syndrome/repurfusion injury
- Metabolic acidosis (acute mineral acidosis)
- Hyerkalemic periodic paralysis (NA+/K+ ATPase dysfunction)
- Drug induced/iatrogenic (propanolol - decreases liver/muscle uptake of K+) - Renal:
- AKI (decreased GFR => decreased K+ excretion)
- CKD end stage
- ureteral obstruction
- Ruptured bladder
- HypoA (decreased Na+/K+ ATPase activation due to reduced aldosterone)
- Drug induced - ACEi, ATII RB, Spironolactone, NSAIDs, Heparin, Cyclosporin, Tacrolimus, TMPS
- Hypoerninemic hypoaldosteronism
- Late pregnancy in greyhounds. (GI fluid loss?) - Spurious:
- Leukocytosis (>100,000 leukocytes/uL)
- Severe thrombocytosis
- haemolysis (Akita/Shiba)
- contaimination with IVFT, EDTA, oxalate
What are the causes of hypokalaemia?
GIT or renal loss.
- Extra renal:
- decreased K+ intake - anorexia, diet, K+ free IVFT
- Increased K+ loss via GIT
2.Translocation extracellular to intracellular fluid:
- Glucose cotnaining fluid with or without insulin
- TPR solution
- Caecholamines (phaeo)
- Hypokalaemic periodic parlaysis - burmese, anomolous activation of Na+/K+ ATPase
Other - albuterol overdose, hypothermia
- Renal:
- CKD
- Distal (type I) RTA
- Proximal (type II) RTA
- DIet induced hypoaleamic nepropathy
- post obstructive diuresis
- osmotic diuresis (DKA)
- Drug induced: diuretics (loop, thiazide), amphotericin B
- hyperA
- hyperaldosteron
- hyperT4
- other: peritoneal dialsys, flurocortisone excess, penicillins, high sodium intake
Kogika VNCA 2017
What is the prevalence of proteinuria in healthy geriatric dogs?
11-15%
Meindl JVIm 2018
What is the sensitivity and specificity of Idex sedivue for the detection of:
- RBc/WBC
- CaOx dihydrate
- Struvite
- Squamous epithelial cells
1. RBc/WBC Sens: 85-90% Spec: 87-90% 2. CaOx dihydrate Sens: 75% Spec: 99% 3. Struvite Sens: 85-90% Spec: 84% 4. Squamous epithelial cells Sens: 33% Spec: 99%
Hernandez JVUM 2017
What is the variability of first morning USG in dogs?
mean difference between min and max for individual dogs was 0.015
mean coefficience of variance 15.4%
- inherent intraindividual variability
Rudinsky JVIM 2019
What mutation is associated with renal cystadenomocarcinoma and nodular dermatofibrosis?
- what breed?
- what is the inheritance pattern?
Folliculin - a tumour suppressor gene, mutation
German Shepherds
dominant inheritance.
What can cause renal amyloidosis?
What does it look like cytologically?
What stain is best to see this?
- Inherited: Shar Pei
- reactive (serum amyloid A accumulation) in abyssinians, idiopthic, infectious, chronic inflam or neoplasia
Cytoogically - undulous, glassy swirls of amorpohous eosinophilic materia in close associated with glomeruli or renal tubular epithelial cells.
Stain with congo red, examine under polaized light => apple green stain
VCNA 2017
What are melamed-Worlinska bodies?
large magenta inclusions within epithelial cells associated with TCC.
VCNA 2017
Are UPC usually higher on home or in clinic samples?
50% higher in clinic samples
Duffy JVIM 2015
Is creatinine or SDMA influence by lean body mass?
SDMA - no
Creatinine - yes. lower LBM => reduced creatinine and risk of falsely overestimating gfr.
Hall JVIM 2015
What proportion of dogs presenting to a cademic medical center have evidence of kidney injury?
In what sub groups was the relative risk higher?
11.5%
geriatric dogs
Babyak JVIM 2017