Chronic Kidney Disease (CKD)

Approach to patient with CKD:
UA, urine lytes, urine protein:creatinine ratio, renal u/s should be ordered on all patients
ANA, complement, Spep/upep can be considered based on history, exam


CKD can be broken down to:
1. Glomerular- nephritic sediment, HTN ie) IgA, PostInfection
2. Tubulointerstitial- Bland sediment, + proteinuria, pyuria, casts ie) chronic obstruction, analgesis
3. Vascular (sm, med, large vessel)-
small vessel disease will have hematuria, proteinuria, HTN.
HTN is an example of medium-vessel disease and is the second most common cause of CKD in the US. Black patients have more aggressive CKD caused by hypertension. Renal artery stenosis is an example of large-vessel disease.
4. Cystic- ua may be normal. Renal ultrasound is key

Management (beyond dialysis)

Among the complications of CKD are anemia, secondary hyperparathyroidism, and bone disease
Anemia is common by stage V CKD. Erythropoeitin Stimulating Agents (ESAs) are indicated once hb<10 but are contraindicated in hb>13. Side effects include HTN, CV disease, thrombosis and must be monitored frequently as should hb to make sure patient still requires ESA.
It is important to maintain iron stores as well (ferritin>100). IDA should be evaluated to exclude hemolysis, blood loss, etc. Dialysis patients may require IV iron in addition to ESA

Hyperparathyroidism is secondary to low Ca, Hi phos states seen in CKD
Vitamin D analogs may replete low 1,25 OH vit D
Phosphate binders are used to reduce phos levels. They may contain Ca, which requires careful monitoring of both Ca and Phos levels.
Although protective initially, unregulated, hi PTH should be lowered to protect bone health among other organs. Calcimimetics like Cinacalcet are used to lower the PTH level, which improves both Ca and Phos levels.

Bone abnormalities in CKD are multifold, but the most common are Adynamic bone disease and mixed osteodystrophy. Careful monitoring of Ca/phos/vitamin D is recommended as this population has a high likelihood of bone disease

(Ellen Eaton MD, 9/14/10)