Management of Children with Chronic Renal Failure: Identifying Intraoral Symptoms and Oral Health Challenges through an Interdisciplinary Approach

Prevalence of renal disease

CRF is a major global health concern, with prevalence estimates ranging from 8-16% worldwide. In adults, the age-standardised prevalence is ∼10.4% for men and 11.8% for women.^[3]

In children, CRF is less well understood and often remains underdiagnosed and underreported, primarily due to its frequent asymptomatic presentation in early stages.^[4] Consequently, many cases are only identified once the condition has advanced significantly.

The incidence of ESRD in the paediatric population is estimated to be between 10 and 12 cases per million children.^[5] The variation in incidence and prevalence of ESRD among children is influenced by several factors. These include racial and ethnic diversity, which affects both the prevalence of CRF and treatment outcomes. The type of renal disease also plays a crucial role in determining disease progression and outcomes. Additionally, disparities in healthcare resources lead to differences in prevalence rates between developed and developing countries. Children in more developed nations, where advanced renal replacement therapies are accessible, typically have better outcomes compared to those in less developed regions with limited healthcare resources.^[6]

Sex differences are also significant, with boys having higher rates of CRF and ESRD compared to girls. This discrepancy is largely due to a higher incidence of congenital conditions such as prune belly syndrome, renal dysplasia, and obstructive uropathy among males.^[7]

Stomatitis and mucosal issues

Around 90% of individuals with renal disease experience oral symptoms due to the disease and its treatments. Uraemia, caused by the buildup of waste products from impaired kidney function, leads to anaemia and pallor of the oral mucosa. This, along with the use of anticoagulants like heparin during haemodialysis, increases the risk of oral complications such as bleeding, petechiae, and ecchymosis.^[12]

Hyposalivation and xerostomia

Hyposalivation is common in renal patients, leading to xerostomia (dry mouth). Symptoms include cracked lips, candidiasis, and a pale, corrugated buccal mucosa. Xerostomia can cause difficulty swallowing, altered taste, oral pain, dental caries, and periodontal issues, affecting quality of life. Studies show that 28-59% of ESRD patients experience xerostomia, often linked to polyuria and kidney dysfunction. Patients may also have halitosis due to high urea levels in saliva, which convert to ammonia, causing uremic fetor.^[13]

Gingival issues

Periodontal diseases in renal patients can lead to complications like abscesses and pulpitis. Gingival enlargement, often caused by medications or transplantation, can affect appearance, dental hygiene, speech, and oral function. In pre-dialysis and dialysis patients, calcium channel blockers are linked to gingival hyperplasia, while kidney transplant recipients may experience it due to immunosuppressants like cyclosporine, which alters fibroblast function and increases tissue growth. Strict oral hygiene is essential to manage gingival overgrowth.^[14]

Oral lichenoid lesions and hairy leukoplakia

Kidney transplant recipients, especially those on immunosuppressive therapies, often develop oral lichenoid lesions and oral hairy leukoplakia. The latter, commonly seen with cyclosporine use, presents as white patches on the tongue due to Epstein-Barr virus reactivation. These lesions can be unilateral or bilateral and may cause discomfort. Drug-induced reactivation of Epstein-Barr virus leads to painless lesions that can result in complications if untreated. Immunosuppression can also increase the risk of oral candidiasis, dysplasia, lip carcinomas, and non-Hodgkin lymphoma.^[15]

Dental calculus and caries

Patients with chronic renal disease often have increased dental calculus due to changes in salivary composition, such as higher pH, lower magnesium, elevated urea, and phosphorus levels. Calcium-phosphorus and calcium oxalate precipitation contribute to calculus formation. While dental caries is less common due to urea’s buffering effect on bacterial biofilm pH, renal patients are still at risk due to poor oral hygiene, a high-carbohydrate diet, and reduced salivary flow. Dental calculus commonly accumulates on the lingual surfaces of lower incisors, near the submandibular gland orifices.^[16]

Halitosis and uraemic frost

Halitosis, or bad breath, is common in renal patients, mainly due to volatile sulphur compounds (VSCs) from oral bacteria. Factors like prostheses, periodontitis, dry mouth, tongue coating, and poor oral hygiene contribute to bad breath in 85% of cases. High blood urea levels, especially over 455 mg/dL, worsen halitosis. Peritoneal dialysis can help by reducing blood urea nitrogen levels. Uremic frost, white patches from urea crystal deposits, may also appear. Over 4% of hemodialysis patients develop angular cheilitis, and antihypertensive medications can cause lichenoid lesions.^[17]

Enamel hypoplasia and structural anomalies

Enamel hypoplasia is common in children with CRF, affecting 31-83% of them. It results from disruptions in enamel formation, causing discoloured or defective enamel on both primary and permanent teeth. The condition appears as white or brown discolorations, indicating damage to ameloblasts or interruptions in enamel maturation from around the 14th week of gestation to the first year of life.^[18]

A total of 37 Children with CRF often have narrowed or calcified tooth pulp chambers and delayed eruption of permanent teeth. ERS, a genetic disorder linked to nephrocalcinosis, worsens dental issues. ERS causes significant enamel abnormalities, such as yellow-brown discolorations and rough surfaces. Despite normal enamel hardness, surfaces may be rough or smooth, with smooth surfaces often linked to microdontia. ERS can lead to enamel reduction or loss in both primary and permanent teeth, along with pulp stones. While nephrocalcinosis is typically asymptomatic, its dental effects are more noticeable.^[19]

Metabolic changes and osteodystrophy

CRF causes metabolic changes and skeletal abnormalities known as metabolic renal osteodystrophy. Key features include bone demineralisation, decreased trabeculation, a “ground-glass” appearance on radiographs, reduced cortical bone thickness, and radiolucent giant cell lesions. Maxillary brown tumours and soft-tissue calcification can also occur. These changes increase the risk of jaw fractures in children with CRF, especially after trauma or oral surgery.^[20]

Dental issues linked to metabolic changes in CRF include tooth movement problems, malocclusion, enamel hypoplasia, abnormal bone repair after extractions, and pulp stones. Radiographs show osteodystrophy as the failure of lamina dura resorption and sclerotic bone around the tooth socket. Oral iron supplements and uraemia can cause tooth discoloration. Other symptoms include pulp constriction, calcification, and regurgitation from nausea due to hemodialysis. Dental erosions, mainly on the lingual surfaces, can result from acid reflux and frequent vomiting linked to electrolyte imbalances.^[21]

Oral health assessment and interventions

Before any surgical intervention, a thorough oral health assessment is essential to mitigate the risk of infections and other complications. Dental procedures should be planned meticulously, with a gradual and well-coordinated approach tailored to each child’s individual needs. Understanding the child’s current renal status, medications, dietary modifications, functional disabilities, and fluid restrictions is also vital.^[23]

Dietary and nutritional considerations

Dietary management plays a significant role in CRF. LPDs can alleviate hyperfiltration, reduce nitrogenous waste, and lessen the renal workload by decreasing glomerular pressure. It is recommended to maintain energy and nitrogen balance by providing 25-35 kcal/kg/body weight/day, thus avoiding malnutrition.^[24] Vitamin D supplementation is often necessary for CRF patients to improve calcium reabsorption and prevent elevated serum parathyroid hormone (PTH) levels and excessive bone turnover.^[25] Additionally, children with CRF should follow a diet low in potassium and sodium.^[26]

The kidney dialysis outcome initiative (KDOQI) and the kidney disease improving global outcomes (KDIGO) guidelines recommend restricting sodium intake for children with hypertension or pre-hypertension. Age-specific upper limits for sodium intake are set at 1500 mg/day for children aged 2-3 years, 1900 mg/day for children aged 4-8 years, 2200 mg/day for children and adolescents aged 9-13 years, and 2300 mg/day for those aged ≥14 years.^[27]

Fluid and electrolyte management

Fluid and electrolyte needs vary based on the child’s primary kidney disease and residual kidney function. Physical examination alone may not detect fluid overload until it reaches severe levels, ∼10% of the child’s body weight.^[27]

Oral hygiene and salivary management

Maintaining optimal oral health is essential, and stimulating salivary production through proper mastication helps. Educating patients and parents on good oral hygiene practices, such as gentle brushing with fluoride toothpaste, flossing, and using mouthwashes to maintain a neutral pH, is crucial. Mouthwashes with 0.12% chlorhexidine can be helpful but may cause taste changes, tartar buildup, and irritation with long-term use. Alcohol-based mouthwashes should be avoided as they can worsen xerostomia, a common issue in CRF patients.^[28]

Fluoride supplementation and follow-up

While fluoride supplements are generally beneficial, their use in CRF patients should be considered cautiously due to the low prevalence of caries in these individuals. Periodic follow-ups are crucial for monitoring and maintaining oral health. For treating enamel hypoplasia, conservative options such as bonded composite restorations or full-coverage restorations may be appropriate.^[22]

Altered pharmacokinetics

Renal impairment significantly affects drug distribution and elimination. In CRF patients, the plasma half-lives of drugs that are primarily excreted through the kidneys can be considerably prolonged. Dialysis helps to shorten these half-lives but does not completely negate the risk of drug accumulation. For medications excreted solely via the renal route, a reduction in creatinine clearance by 50% theoretically doubles the elimination half-life of the drug. To prevent excessive drug accumulation, dose adjustments must be made based on the severity of renal impairment. It is essential to avoid nephrotoxic drugs and to use narcotic medications cautiously in patients with anaemia, as these can exacerbate respiratory issues.^[10]

Corticosteroid use and adrenal crisis

For patients undergoing invasive dental procedures who are also on corticosteroids (such as those with nephrotic syndrome), appropriate corticosteroid coverage is necessary to minimise the risk of adrenal crisis.^[29] This precaution ensures that the patient’s adrenal function is adequately supported during stressful situations, including dental interventions.

Antibiotic prophylaxis

Antibiotic prophylaxis is often recommended before invasive dental procedures to reduce the risk of infections.^[30] Maintaining proper oral hygiene reduces the likelihood that an infection will spread and, as a result, sepsis, endocarditis, or enteritis will not manifest.^[31] Patients with active renal impairment should take antibiotics prior to any oral surgical operation.^[32]

Local anesthesia considerations

The use of local anesthesia containing adrenaline (epinephrine) must be approached with caution in CRF patients. Adrenaline can increase the risk of cardiac arrhythmias, particularly in those with compromised renal function. Although not absolutely contraindicated, its use requires careful assessment of the patient’s overall clinical condition, with close monitoring of blood pressure, heart rate, and electrolyte levels.^[33]

Bleeding and infection management

Effective at-home oral hygiene, combined with in-office care, is crucial in reducing the risk of infection. Patients on dialysis, who are at higher risk for bleeding and infection, require special consideration during dental treatment planning. Those with significantly prolonged bleeding or clotting times, or who are on antifibrinolytics, fresh-frozen plasma, vitamin K, or platelet replacement therapy, may need additional interventions to control bleeding. Techniques such as administering specific medications or using electrocautery can help manage bleeding during invasive dental procedures.^[34]

The drugs that are indicated/contraindicated or can be administered after modification are given in Table 1.^[29]

One of the absolute contraindications for patients with renal disease is surgical procedures requiring general anaesthesia. Patients with severe renal disease may not tolerate the physiological stress of general anaesthesia, and there may be an increased risk of complications, such as fluid shifts and electrolyte imbalances. Major surgeries are complicated by hyperkalaemia due to tissue damage, acidemia, and blood transfusion. It predisposes patients to dysarrhythmias and cardiac arrest. Dental implant placement, high risk endodontic procedures involving extensive manipulation of tooth structures or the periapical region, and extensive oral surgical procedures can also be relatively contraindicated.

Infection risks and transfusion concerns

Patients undergoing dialysis are at increased risk of contracting infectious diseases such as HIV and hepatitis B and C due to frequent transfusions and immunosuppressive treatments associated with renal failure. This heightened risk necessitates vigilant infection control measures and thorough patient history assessments to identify any potential exposures or infections.^[30]

Management of bleeding risks

Patients with renal failure on hemodialysis are at increased risk of bleeding and infections due to anticoagulants and continuous vascular access. Dentists should consider the dialysis schedule when planning treatments. Elective procedures should ideally be scheduled the day after dialysis to allow toxin removal, stabilise intravascular volume, and manage heparin by-products. For patients with prolonged bleeding or clotting times, or those on antifibrinolytics, additional measures like medication adjustments or electrocautery may be needed to control bleeding during invasive procedures.^[34]

Considerations for general anaesthesia and surgical procedures

General anaesthesia carries significant risks for patients with severe renal disease, as they may struggle with fluid shifts, electrolyte imbalances, and hyperkalemia, which can lead to dysarrhythmias and cardiac arrest. As a result, major surgeries requiring general anaesthesia are generally contraindicated. Similarly, high risk dental procedures, such as dental implants, extensive endodontic treatments, or major oral surgeries, may also be contraindicated due to these risks.^[35,36]