renal dx Flashcards
Kidney Structure
nephron structure
glomerulus
where filtration occurs
afferent vs efferent arteriole
afferent: towards
efferent: away
bp affect at glomerulus
will influence filtration= too high will reduce function (hypertensive)
glomerular filtration
The hydrostatic pressure gradient forces glomerular filtration.
20% of renal plasma flow is filtered into Bowman’s capsule; hemodynamic factors contribute
to the filtration rate
influences of GFR
Glomerular Filtration Rate (GFR) affected by renal artery pressure other autoregulation factors of GFR:
1. vasoreactive (myogenic) reflex of afferent arteriole
2. tubuloglomerular feedback (TGF)
3. angiotensin II-mediated vasoconstriction of the efferent arteriole
. vasoreactive (myogenic) reflex of afferent arteriole
- causes dilatation or constriction of the afferent arteriole to maintain stable glomerular pressure in response to variations in systole
- tubuloglomerular feedback (TGF)
- causes dilatation or constriction of the afferent arteriole to maintain stable glomerular pressure in response to solute concentration changes detected by the macula densa cells in the distal/ascending Loop of
Henle
Ang II GFR effect
- angiotensin II-mediated vasoconstriction of the efferent arteriole
where resorb, secrete, filter and excrete happen at nephron
Kidney Functions
- Water regulation
- Electrolyte regulation
- Extracellular volume/pressure regulation
- Acid-base homeostasis
- Endocrine/metabolic
- Blood plasma filtration
- Excretion of metabolic waste
- Urine production
- Prostaglandin production
endocrine kidney functions
oKinins
oErythropoietin
oPhosphate
oVitamin D
oRenin
plasma filtration at kidney
oGlucose and amino acid reabsorption
oCalcium and phosphate regulation
Acute Kidney Injury (AKI)
A condition in which the kidneys suddenly can’t filter waste from the blood
Acute renal failure develops rapidly over a few hours or days. It may be fatal. It’s most common in those who are critically ill and already hospitalized
AKI uremia
Uremia results from the cumulative effects of renal failure, retention of excretory products,
and interference with metabolic and endocrine function
acute vs chronic renal more common?
chronic
symptoms AKI
decreased urinary output
swelling due to fluid retention
nausea
Fatigue
shortness of breath.
Sometimes symptoms may be subtle or may not
appear at all.
causes of ARF locations
- Pre-renal
- Intrinsic Renal
- Post-renal
pre renal ARF causes
what Rx can cause ARF
**ACE-I: **monopril, captopril, enalapril
ARB: angiotensin receptor blocker, (Diovan, Cozaar, Benicar);
NSAIDs:Indomethacin
PPI: proton pump inhibitors Prilosec, Prevacid &
Nexium (also linked to stomach cancer)
why would anti hypertensives cause ARF?
throw off autoregulation of the MD cells
TTP-HUS
thrombotic thrombocytopenic purpura–hemolytic-uremic syndrome.
can lead to ARF
intrinsic causes ARF
post renal causes ARF
ARF tx
address the underlying cause
fluids
medication
dialysis.
Chronic Kidney Disease causes (examples)
*Chronic Glomerulonephritis
*Systemic Lupus Erythematosus
*Neoplasms (MM)
*Polycystic kidney disease
*AIDS nephropathy
*Diabetic nephropathy
*Etc. (many others)
risk factors of chronic kidney dx
- Age (≥60 years of age)
- Smoking
- Obesity
- HTN: poorly controlled
- Diabetes : 40-50% of patients with type 2 DM
- Nephrotoxins/Drugs
- Infections
- Low birthweight
- Chronic Inflammation
diabetic kidney dx pathogenesis
Chronic Kidney Disease diagnostic criteria
Glomerular Filtration Rate (GFR):
Urinary albumin/creatinine ratio:
Urinary albumin excretion rate:
Glomerular Filtration Rate (GFR): <60 ml/min/1. 73 m2
Urinary albumin/creatinine ratio: ≥ 30 mg/g
Urinary albumin excretion rate: ≥ 30 mg/day
Diagnosis and Classification of CKD are based on:
GFR and albuminuria/proteinuria
End-Stage Renal Disease (ESRD)
* GFR value?
* Requires what tx
- GFR <15 ml/min/1.73 m2
- Requires kidney replacement therapy (hemodialysis, transplantation)
GFR with age
decreases
severely decreased GFR level
15-29mL/min/1.73m2
CKD and fluid/electro balance
I. Fluid and electrolyte imbalance
* Dysregulation of Na+, K+ and H2O reabsorption
* Hyperkalemia
* Edema
CKD and hypertension
Hypertension
* RAS activation
* Aldosterone and catecholamine activation
* Hypervolemia
CKD with CV and endocrine
III. Cardiovascular Disease
IV. Endocrine dysfunction
CKD anemia
Anemia [Hb <12 g/dl (F); <13.5 g/dl (M)]
* Decreased Epo and RBC survival
* Impaired iron absorption (insufficient hepcidin),
blood loss (dialysis)
* Normocytic, normochromic anemia
CKD and uric acid
uric acid) and Uremia (urea)
CKD dyslipidemia
- Dysregulated metabolism of lipid and uremic toxin-mediated lipid alterations
- Atherosclerosis
CKD can lead to acidosis or alklosis
Metabolic acidosis
* Decreased excretion of NH4+
* Decreased absorption of H+ and HCO3-
CKD Mineral bone disorder (MBD)
Mineral bone disorder (MBD)
* Decreased vitamin D levels
* Dysregulation of Ca2+ and PO4-3
* Increased PTH and FGF23 levels
* Renal Osteodystrophy, secondary hyperparathyroidism
* Calciphylaxis –extraosseous calcifications
➢Blood vessels of dermis & subcutaneous fat
CKD mineral bone disorder oral sign
may see browns tumros due to hyperPTH
CKD diabetic management factors to control
- Control DM
- Control HTN
- Control HLD
- Diet/lifestyle modification
- Management of other comorbidities and complications
CKD DM control
HbA1 <8%
HTN control CKD DM
Control HTN –BP <140/90 mm Hg
* Cardioselective beta-blocker
* Diuretics
* ACE inhibitor
* ARB
* Calcium channel blocker
HLD control CKD DM
LDL <100mg/dl
CKD oral manifestations
Xerostomia/dry mouth
Halitosis
Dysgeusia
Infections
Enamel defects (children)
Uremic stomatitis (rare)
Petechiae and ecchymosis
Osteodystrophy
CKD dysguesia
metallic taste
CKD oral infections
- Opportunistic
- Periodontal
- Odontogenic
- Salivary
when would uremic stomatitis be seen with CKD
BUN >55 mg/dl
CKD osteodystrophy
- Lack of hydroxylation of 25(OH)D to 1,25(OH)2D which takes place in the kidneys
- Causes lack of Ca+ absorption from intestines
- Stimulates parathormone secretion and Ca+ loss from bone
- Inhibits bone mineralization
Osteodystrophy Causes in oral cavity
- Loss of lamina dura
- Demineralization (“ground-glass”)
- Expansile radiolucencies (CGCG, brown tumor)
- Wide trabeculae
- Loss of cortication
- Sclerosis
compare
ground glass- osteodystrophy
ground glass osteodystrophy
CKD dialysis modalities
hemodialysis and peritoneal
hemodialysis
- Arteriovenous fistula
- Ateriovenous graft
- Central venous catheter (special, short-term)
- Machine filters blood
- Heparin is typically used
- Every 2-3 days; 3-4 hours/session
- Risk of infectious disease –Hep B; Hep C
hemodialysis and dental tx
Dental treatment planned for the
day AFTER hemodialysis
Peritoneal dialysis
- Hypertonic solution in peritoneal cavity
- Peritoneal membrane used for exchange
- 3-5x/day or overnight
forms of access for dialysis
Arteriovenous Fistula and Arteriovenous
Graft use may lead to:
difigurements
organ transplant matching
- ABO matching
- HLA matching
organ transplant life expectancy/ organ sources
- > 5- year life expectancy
- Can be from live (better) or deceased donor
oRelated mismatched donor (3/6 match) is better
than deceased donor
contraindications to transplant
- AIDS
- Active hepatitis
organ rejection
- Activated cytotoxic T cells (direct)
- Alloantibodies (direct)
- Delayed type hypersensitivity –arteriosclerosis of
transplant (indirect)
trnasplants req what tx
immunsupression
stages of immunosupp tx
Induction (prevent acute rejection)
Maintenance (unless identical twin)
induction Rx
- Antithymocuyte globulin
- Alemtuzumab (anti-CD52)
maintenance Rx
Azathioprine
Mycophenolate mofetil
Calcineurin inhibitors
Steroids
mTOR inhibitors (mTORi)
Belatacept
* Azathioprine- Antimetabolite
o** Inhibits DNA and/or RNA synthesis**
* Mycophenolate mofetil- Similar to azathioprine
o **Less bone marrow suppression **
-
Steroids **
oLow dose**, adjunct -
Calcineurin inhibitors: Cyclosporine and Tacrolimus
oBoth decrease production of** IL-2 mRNA and proinflammatory cytokines**
oDiabetes and nephrotoxicity complications -
mTOR inhibitors (mTORi): Sirolimus, Everolimus
o**Inhibits T cell proliferation signaling **
* Belatacept
* Binds costimulatory molecules
* **T cell anergy and apoptosis **
Important adverse effects of immunosuppression
- Cytopenias (bone marrow suppression)
➢ Bleeding- Severe thrombocytopenia <50K
➢ Susceptibility to infection- Severe leukopenia/ neutropenia
oWBC <2000
oANC <500 - Increased risk of developing skin and hematologic cancers
oral adverse effects of immunosuppression
- Gingival hyperplasia (cyclosporine)
- Aphthous-like ulcers (mTORi)
values to determine level of renal impairment and disease control
- BP –Avoid arm with AV shunt when measuring BP
- GFR
- BUN
- Creatinine clearance
- Serum creatinine
- Electrolytes
assessing bleeding with renal pts
- Patients can be at risk for both bleeding and thrombosis
- Quantitative and qualitative platelet impairment
➢ Platelet count
➢ PT-INR
➢ PTT - Hemostatic measures as necessary
- Be aware of signs and symptoms of thrombosis
- Referral to a specialized center as necessary
infection control with renal pts
* Advanced uremia →?
* Treat infections how?
* If invasive procedures in patients with stage 4 (severe) or end-stage renal disease →?
* Antibiotic prophylaxis IS NOT routinely necessary for?
* Antibiotic prophylaxis may be necessary for patients with?
* Antibiotic prophylaxis is necessary in hemodialysis patients if performing?
- Advanced uremia →decreased immune function
- Treat infections aggressively
- If invasive procedures in patients with stage 4 (severe) or end-stage renal disease →
consult physician about need for antibiotics - Antibiotic prophylaxis IS NOT routinely necessary for peritoneal dialysis
- Antibiotic prophylaxis may be necessary for patients with a synthetic AV graft
- Antibiotic prophylaxis is necessary in hemodialysis patients if performing incision and
drainage
drug effects with renal pts
* Check drug ________ mechanism
* Caution with?
* Carefully review possible_______ with current medication list when prescribing new medications
* Consult with?
- Check drug excretion mechanism
- Caution with nephrotoxic drugs (acyclovir, NSAIDs, aspirin, aminoglycosides, tetracycline)
- Carefully review possible drug interactions with current medication list when prescribing new medications
- Consult with patient’s physician
preffered analgesic with renal pts
acetaminophen
Acetaminophen with renal pts
- Nephrotoxic at high doses
- Increase dosing interval
oq6h (GFR >10 but <50ml/min)
oq8hs (GFR <10ml/mim)
NSAIDs and renal pts
**AVOID **
* Except for aspirin for CVD
* Especially long-term use
* Interaction with antihypertensives
* Impairment of prostaglandin production
➢ Vasoconstriction, reduced renal perfusion
opioids and renal pts
AVOID
* Risk for accumulation of toxic metabolites
* Tramadol with dose adjustment and/or increased dosing interval
* Consult with physician
Benzodiazepines with renal pts
CAUTION
* Consider half-life, active metabolite
* Single dosing, consult with physician
Acyclovir
renal pts
- Increase dosing interval q8h or q12h
Abx not req adjustment with renal pts
oClindamycin
oDoxycycline
oErythromycin
oMetronidazole
Abx req adjustment with renal pts
oAmoxicillin
oCephalexin
oAzithromycin
oAmoxicillin –q12h or q24h
oCephalexin –q6-18h or q12-24 h
oAzithromycin –avoid if GFR <10
antifungal agents and renal pts
Fluconazole
* Reduce to 50% or 25% of original dose
Nystatin –No adjustment
Goals of pre-transplant dental clearance
Remove active foci of infection and limit potential foci of infection (think 6 months)
*Treat active foci of infection
oSRP
oEndodontic treatment
oRestorations
*Extract teeth with questionable (even if in your opinion minimally)/poor prognosis
*Assess caries risk and need for adjuncts (fluoride)
*Educate patient on importance of maintaining good homecare, diet and professional maintenance
Take into account patient compliance and, unfortunately, patient economics when planning treatment
post transplant tx
Defer elective treatment within first 6 months post-transplant
* Emergency care only –consider specialized center
dental maintance surveillance
* Opportunistic infections
* Toxicities/side effects of systemic treatment
* Cancer
- Opportunistic infections (odontogenic, candidiasis, aspergillosis, HSV, OHL, CMV)
- Toxicities/side effects of systemic treatment
oAdrenal insufficiency –long-term high-dose corticosteroids
oGingival hyperplasia - cyclosporine
oPyogenic granuloma and OFG-like lesions - tacrolimus
oOral ulcerations –sirolimus - Cancer
oNon-melanoma skin cancer (basal cell and squamous cell carcinoma [SCCa])
oPost-transplantation lymphoproliferative disorder (frequently EBV associated, B cell)
oOther solid cancers including oral SCCa
