3. Functions of the Kidneys
Nonexcretory functions
Degradation of polypeptide hormones
Insulin
Glucagon
Parahormone
Prolactin
Growth hormone
Antidiuretic hormone
Gastrin
Vasoactive intestinal polypeptide
Synthesis and activation of hormones
Erythropoietin (stimulates erythrocyte production
by bone
marrow)
Prostaglandins (vasodilators that act locally to prevent renal
ischemia)
Renin (important in regulation of blood pressure)
1,25-Dihydroxyvitamin D3 (final hydroxylation of vitamin D to
its most potent form)
Excretory functions
Excretion of nitrogenous end products of protein metabolism
(e.g., creatinine, uric acid, urea)
Maintenance of ECF volume and blood pressure by altering
Na+
excretion
Maintenance of plasma electrolyte concentration within
normal
range
4. Maintenance of plasma osmolality by altering water excretion
Maintenance of plasma pH by eliminating excess H+ and
regenerating HCO3
–
Provision of route of excretion for most drugs
Abbreviations: ECF, extracellular fluid; H+, hydrogen; HCO3
–,
bicarbonate; Na+, sodium; pH, hydrogen ion concentration
Functions of the Kidneys
5. DIAGNOSTIC PROCEDURES IN
Serum Chemistry
In the presence of renal dysfunction, changes in homeostasis
are reflected in serum chemistry. Sodium, chloride, blood urea
nitrogen (BUN), glucose, creatinine, carbon dioxide, potassium,
phosphate, and calcium levels provide a useful tool to
evaluate the degree of renal impairment and disease progression.
Serum creatinine and BUN are often important markers
to the GFR. Both of these products are nitrogenous waste
products of protein metabolism that are normally excreted in
the urine, but they may increase to toxic levels in the presence
Urinalysis
Creatinine Clearance Test
Renal Ultrasonography
Biopsy
Magnetic Resonance Imaging
Computed Tomography
Intravenous Pyelography
Nuclear Medicine (Radionuclide
Scintigraphy)
14. Oral and Radiographic Manifestations of Renal
Disease and Dialysis
Oral manifestations
Enlarged (asymptomatic) salivary glands
Decreased salivary flow
Dry mouth
Odor of urea on breath
Metallic taste
Increased calculus formation
Low caries rate
Enamel hypoplasia
Dark brown stains on crowns
Extrinsic (secondary to liquid ferrous sulfate therapy)
Intrinsic (secondary to tetracycline staining)
15. Dental malocclusions
Pale mucosa with diminished color demarcation
between
attached gingiva and alveolar mucosa
Low-grade gingival inflammation
Petechiae and ecchymosis
Bleeding from gingiva
Prolonged bleeding
Candidal infections
Burning and tenderness of mucosa
Erosive glossitis
Tooth erosion (secondary to regurgitation
associated with
dialysis)
Dehiscence of wounds
Oral manifestations
16. Radiographic manifestations
Demineralization of bone
Loss of bony trabeculation
Ground-glass appearance
Loss of lamina dura
Giant cell lesions, “brown tumors”
Socket sclerosis
Pulpal narrowing and calcification
Tooth mobility
Arterial and oral calcifications
24. Summary of Dental Considerations and
Management of the Patient With Renal Disease
Before treatment
Determine hemodialysis schedule and treat on day after
hemodialysis. No such concerns with peritoneal dialysis.
Consult with the patient’s nephrologist for recent
laboratory tests
and discussion of antibiotic prophylaxis in presence of
prior
infective endocarditis.
Identify arm with vascular access and type; notate in chart
and avoid taking blood pressure measurement/injection of
medication on this arm.
Evaluate patient for hypertension/hypotension routinely.
Institute preoperative hemostatic aids (DDAVP, conjugated
estrogen) when appropriate.
Determine underlying cause of renal failure (underlying
disease may affect provision of care, e.g., diabetes
mellitus,
hypertension).
Obtain routine annual dental radiographs to establish
presence and
follow manifestations of renal osteodystrophy
25. Consider routine serology for HBV, HCV, and HIV
antibody.
Consider antibiotic prophylaxis when appropriate
according to
current AHA guidelines.
Consider sedative premedication for patients with dental
anxiety
and elevated BP or history of unstable angina. Discuss
with
patient medication adherence counseling.
During treatment
Perform a thorough history and physical examination for
the
presence of oral manifestations.
Aggressively eliminate potential sources of
infection/bacteremia.
Use adjunctive hemostatic aids during oral/periodontal
surgical
procedures.
Maintain the patient in a comfortable uncramped position
in the
dental chair.
Allow the patient to walk or stand intermittently during long
procedures.
26. After treatment
Use postsurgical hemostatic agents.
Encourage meticulous home care and hygiene.
Institute therapy for xerostomia/salivary gland
hypofunction when
appropriate.
Consider use of postoperative antibiotics for traumatic
procedures
if uremic.
Cautious use of respiratory-depressant drugs in the
presence of
severe anemia.
Adjust dosages of postoperative medications according to
the
extent of renal failure.
Ensure routine recall maintenance.
