Chronic Kidney Disease Following Acute Flank Pain in a Young Patient with Multiple Connective Tissue Disorders

Case at a Glance

A 28-year-old female with multiple connective tissue disorders presented with acute onset left flank pain, fatigue, and declining kidney function, leading to a diagnosis of chronic kidney disease stage 3. Despite partial recovery, the underlying etiology remains unclear.

Patient's Story

The patient, a 28-year-old woman (5'2", 115 lbs) with a complex medical history including Ehlers-Danlos syndrome hypermobility type, PCOS, Raynaud's phenomenon, POTS/dysautonomia, MCAS, atopic dermatitis, and suspected mixed connective tissue disease, presented with sudden onset of chronic left flank pain accompanied by overwhelming fatigue and severe loss of stamina. Her symptoms developed acutely without apparent precipitating factors.

Initial Assessment

Laboratory studies revealed significant decline in kidney function with eGFR dropping to 50 mL/min/1.73m² (normal >90). The patient reported persistent left-sided flank pain and constitutional symptoms including marked fatigue and exercise intolerance. Physical examination findings were consistent with her known connective tissue disorders.

The Diagnostic Journey

Renal ultrasound was performed showing apparent morphological differences between the left and right kidneys, though formal radiology reports were referenced by physicians rather than direct image interpretation. Multiple healthcare providers acknowledged abnormal findings but were unable to establish a definitive diagnosis. Nephrology consultation confirmed renal dysfunction but provided limited diagnostic clarity with extended follow-up intervals.

Final Diagnosis

Chronic Kidney Disease Stage 3 (eGFR 50-60 mL/min/1.73m²) of unknown etiology, possibly related to underlying connective tissue disorder or unidentified acute kidney injury with incomplete recovery.

Treatment Plan

Conservative management with nephrology follow-up every 6 months. Current medications include spironolactone 100mg daily and amphetamine 15mg daily. No specific renal-protective interventions were initiated due to unclear etiology.

Outcome and Follow-up

Partial improvement noted after 4 months with eGFR recovery to 60 mL/min/1.73m² and some resolution of systemic symptoms. At 11-month follow-up, patient continues to experience intermittent flank pain with persistently elevated creatinine and reduced eGFR. The patient expresses frustration with lack of definitive diagnosis and requests more aggressive diagnostic workup to determine underlying cause of kidney dysfunction.