Beware of the rapidly rising creatinine in diabetic patients.A 73-year-old woman with a longstanding history of type 2 diabetes type 2 diabetes
See diabetes mellitus. , complicated by hypertension and hypercholesterolaemia, presented to the casualty department with a 3-week history of malaise, worsening cough with dyspnoea dyspnoea
dyspnea. and episodic minor haemoptysis. She had good glycaemic control; her most recent Hb[A.sub.1C] was 7.1.
Examination revealed a blood pressure of 160/85 mmHg, grade 1 hypertensive retinopathy and features of congestive con·ges·tive
Of or characterized by congestion.
pertaining to or associated with congestion. See also congestive heart failure. cardiac failure (CCF), but mild pulmonary oedema. She did not have a peripheral neuropathy.
Biochemistry showed markedly abnormal renal function (Table I) and a normocytic anaemia (Hb 7.4, mean corpuscular volume mean corpuscular volume
n. Abbr. MCV
The average volume of red blood cells in erythrocyte indices, calculated from the hematocrit and the red blood cell count. 90.0). Ultrasound showed normal-sized kidneys. No urinalysis was documented. She was assessed as having worsening CCF and chronic renal failure chronic renal failure Chronic kidney failure Nephrology A slow decline in renal function, which may be 2º to chronic HTN, DM, CHF, SLE, or sickle cell anemia and, if extreme, leads to ESRD, mandating kidney dialysis; an abrupt decline in renal function may be secondary to longstanding diabetes and hypertension, and was admitted for symptomatic treatment and subsequently discharged.
A month later her symptoms had worsened and her creatinine had doubled (Table I). She was admitted to the renal unit with a similar clinical picture. Urinalysis showed an active urine with blood, red cell casts and heavy proteinuria proteinuria /pro·tein·uria/ (-ur´e-ah) an excess of serum proteins in the urine, as in renal disease or after strenuous exercise.proteinu´ric
1. . Renal biopsy showed fibrocellular crescents and little evidence of diabetic glomerulosclerosis (Fig. 1). Serology results showed a markedly elevated p-ANCA (352). ANCA-associated rapidly progressive glomerulonephritis rapidly progressive glomerulonephritis Crescentic glomerulonephritis, membranous glomerulonephritis, necrotizing glomerulonephritis Nephrology A type of kidney disease characterized by a rapid loss of renal function, with crescent-shaped deposits in at least 75% of was diagnosed and she was immediately started on corticosteroids and cyclophosphamide. Despite immunosuppressive therapy and acute dialysis, there was no improvement in renal function.
[FIGURE 1 OMITTED]
This case illustrates the importance of being aware of non-diabetic renal disease in the diabetic patient (incidence between 10% and 30%).
Diabetic nephropathy shows:
* strong concordance with retinopathy and neuropathy
* the hallmark finding of an inactive urine with heavy proteinuria.
Diabetic patients with rapidly deteriorating renal function, in the setting of good glycaemic control, the absence of diabetic retinopathy and an active urine (blood and cellular casts), warrant further investigation for non-diabetic and potentially treatable renal diseases. Early identification and treatment is essential as outcome is dependent upon initial glomerular filtration rate glomerular filtration rate
n. Abbr. GFR
The volume of water filtered out of the plasma through glomerular capillary walls into Bowman's capsules per unit of time. and extent of chronic histological changes at biopsy.
J G PETER, MB ChB CRS SWANEPOEL, MB ChB, FRCP (Edin)
Division of Nephrology
Department of Medicine University of Cape Town and Groote Schuur Hospital
Table I. Renal function Date 10/01/05 27/06/05 03/05/06 Urea 7.3 9.1 17.8 Creatinine 89 88 489 Date 29/05/06 12/6/06 13/06/06 Urea 29.8 30.4 31.6 Creatinine 820 879 920