Treatment of Renal Medullary Pyramid Disease
For renal medullary pyramid disease, treatment must be targeted to the specific underlying condition causing the damage, as there is no universal approach for all medullary pyramid pathologies.
Specific Disease Entities Affecting Renal Medullary Pyramids
Renal Medullary Carcinoma
- Platinum-based chemotherapy regimens are the preferred treatment for renal medullary carcinoma, which is an extremely rare and aggressive form of kidney cancer 1
- Gemcitabine in combination with carboplatin or cisplatin, or paclitaxel with carboplatin, have shown partial responses 1
- Oral targeted therapies generally do not produce responses in patients with renal medullary carcinoma 1
- Prognosis remains dismal despite treatment, with most patients presenting with metastatic disease at diagnosis (67-95% of cases) 1
Tumor Lysis Syndrome Affecting Medullary Vessels
- Aggressive hydration with intravenous fluids to maintain urine output of at least 100 ml/hour (3 mL/kg/hour in children <10 kg) 1
- Rasburicase administration for rapid degradation of uric acid 1
- For hyperphosphatemia, aluminum hydroxide at 50-100 mg/kg/day divided in 4 doses 1
- Hemodialysis when crystallization occurs in collecting ducts and medullary vessels causing acute renal failure 1
- Early initiation of renal replacement therapy to remove purine by-products and correct electrolyte abnormalities 1
Medullary Nephrocalcinosis
- Treatment depends on the underlying cause (distal renal tubular acidosis, vitamin D toxicity, or tubulopathies) 2
- Ultrasonography is important for early diagnosis, as X-rays detect medullary calcinosis in only 24% of cases 2
- For medullary sponge kidney with nephrolithiasis, address specific metabolic abnormalities: hypercalciuria (58%), low urine volume (35%), hyperuricosuria (27%), hypocitraturia (19%), elevated urine sodium (15%), and hyperoxaluria (12%) 3
Bartter Syndrome (Affecting Salt Reabsorption in Medullary Thick Ascending Limb)
- Sodium chloride, potassium chloride, and fluid supplementation adjusted individually based on symptoms and severity 1
- Nonsteroidal anti-inflammatory drugs (NSAIDs) are a mainstay of treatment, especially during the first years of life (except in transient BS5) 1
- Monitor for and treat hypercalciuria and nephrocalcinosis, which are typical in some forms 1
Treatment Approach Based on Pathophysiology
For Inflammatory/Fibrotic Changes
- Hyperechogenic "rings" in the peripheries of renal medullary pyramids may indicate fibrosis with or without calcifications 4
- Treatment should target the underlying kidney disease, as 90% of patients with this finding have evidence of renal disease 4
For Traumatic Injuries
- Most blunt renal injuries can be managed non-operatively 1
- Percutaneous angioembolization is increasingly accepted for treating ongoing bleeding without surgical exploration 1
For Malignant Hypercalcemia Affecting Medullary Function
- Aggressive intravenous rehydration with normal saline to correct hypovolemia and promote calciuresis 5
- Denosumab is preferred in patients with renal insufficiency where bisphosphonates may be contraindicated 5
- Renal replacement therapy when severe hypercalcemia persists despite standard medical therapy 5
- Use calcium-free or low-calcium dialysate solution for dialysis 5
Monitoring and Follow-up
- For patients with renal medullary carcinoma receiving systemic therapy, history and physical examination every 6 to 16 weeks 1
- Imaging tests such as CT or MRI before starting systemic treatment and every 6 to 16 weeks thereafter, adjusted according to disease progression 1
- For medullary sponge kidney, monitor for recurrent stone events, which occur in approximately 33% of patients with nephrolithiasis 3