AKI in a patient with
known multiple
myeloma
James Alva
PGY-1
Learning objectives
• To understand the various causes of AKI, and how to identify
pre-renal vs intrinsic renal.
• To identify the possible sources of AKI in patients with
Multiple myeloma, and their pathogenesis.
HPI
• 76 y/o F with PMH of IgG multiple myeloma on
velcade/decadron, CHF (EF 30%), CAD, MI s/p PCI
• P/w
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Diarrhea x 2 months. Non-bloody
Vomiting x 1 day. Non-bloody, non-bilious.
Generalized malaise x 2 days
Abnormal clinic results
• BUN/Cr: 15/2.25
• Baseline Cr: 1.08
History
• PMH:
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IgG MM
NSTEMI s/p PCI
CHF 30%
HLD
• Medications
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Coreg: 6.25 mg BID
Lipitor: 40 mg once daily
Plavix 75 mg once daily
ASA 81 mg once daily
Lisinopril 5 mg once daily
Nitroglycerin PRN chest pain
• Allergies: NKA
• Social: Denies smoking. Social drinking (rare), no recreational drugs
• ROS: Negative
Physical exam
• Vitals:
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T: 36.5
HR: 125
BP: 98/67
RR: 16
O2 sat: 98
General: Well appearing, NAD
Neuro: AOx3
Neck: Supple, no JVD, trachea midline
Cardio: Tachycardic. Normal S1, S2, no m/r/g
Lungs: CTAB, no r/w/r
Abdomen: Obese, soft, non-tender, non-distended
Extremities: Full ROM, 5/5 UE, LE, trace edema
Labs/Imaging
• CBC
• WBC:5.83, H/H: 10.6/32.3, Plt:337
• Chem
• Na:142, K:3.3, Cl:106, Bicarb:22, BUN/Cr: 17/2.38
• GFR: 24, Ca: 9.4
• U/A: Neg.
• Urine chem: Na: 28, K: 13.1, Cl: 45, Cr: 60.5
• Osm: 202
• Renal ultrasound: Unremarkable. No obstruction
AKI
• Definition
• RIFLE: Increase in serum Cr > 50% over < 7 days
• AKIN: Increase in Cr: > 50%
• OR increase in serum Cr: 0.3 mg/dl in < 48 hrs.
• KDIGO: Increase in Cr > 0.3 mg/dl over 48 hours
• OR > 50% increase over 7 days
• Various staging within each criteria
Types of AKI
Calculations
• FENA: (Una)/(Pna)/(Ucr)/(Pcr) x 100
• 0.78%  Pre-renal
• BUN/Cr ratio
• 7.14  Intrinsic
Causes of AKI
• Prerenal
• Hypovolemia, CHF, medications, hypotension, Renal artery
obstruction, cirrhosis
• Intrinsic renal
• Tubular disease (ATN), glomerular disease, vascular disease,
malignancy, interstitial disease
• Postrenal
• Urethral obstruction, obstruction of solitary kidney, obstructing
neoplasm, retroperitoneal fibrosis, ureteral obstruction*
Multiple myeloma
• Common findings
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African American
IgG, IgA
Anemia
Renal failure*
Recurrent infections
• Decreased normal immunoglobulins
• Cord compression
• Plasmacytoma or spinal fractures
Multiple myeloma renal disease
• Renal failure may be initial manifestation
• >2.0 mg/dl in 20%
• Causes:
• Light chain cast nephropathy (myeloma kidney)
• Direct damage and occlusion in ascending loop of henle
• Tamm-Horsfall mucoprotein
• Amyloidosis
• Light chains taken up and metabolized by macrophages, secreted, and
precipitate: Congo red-positive B-pleated fibrils.
• Monoclonal immunoglobulin deposition disease
• Light chain/heavy chain fragments. Congo red negative.
• Renal tubular dysfunction
• Reabsorption and accumulation of light chains in proximal tubular cells.
Fanconi syndrome. Exacerbates light chain cast nephropathy.
• Other causes
Other causes
• Hypercalcemia
• 15% of patients >11.0 mg/dl at diagnosis
• Renal vasoconstriction via intratubular calcium deposition.
• Nephrogenic diabetes insipidus
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Reversible
• IV radiocontrast
• Rare. 1.5% of pts
• Due to Hypovolemia and light chain deposition
• Interaction between contrast and light chains
• Drugs
• NSAIDs
• Bisphosphonates
• Assd. With ATN and focal/segmental glomerulosclerosis
• Bortezomib
• Treatment for myeloma kidney, but may be assd. With other causes of renal failure
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RARE. Bilateral hydronephrosis, nephrolithiasis, renal failure.
• Lenalidomide
• Renal failure 4-10% of pts.
• Lisinopril
• Elevated BUN/Cr common. AKI rare.
Labs cont.
• Immunoglobulins:
• IgA: 70
• IgM: 60
• IgG: 807
• Free light chains
• Kappa: 12.4
• Lambda: 16.6
• C. Dif: Neg.
Intervention
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Patient given 2 L IV fluids in ER, 1 L as inpatient
Lisinopril d/c
Loperamide started
Creatinine (1.08 baseline)
• Cr: 2.38  1.71  1.68
• AKI 2/2 to hypovolemia
• Prolonged hypovolemia, hypotension, CHF  ischemic injury 
pre-renal, intrinsic renal failure findings
References
• Agabegi, Steven S., Elizabeth D. Agabegi, and Adam C.
Ring. Step-up to Medicine. Philadelphia: Wolters
Kluwer/Lippincott Williams & Wilkins, 2013. Print.
• Cline, David. Tintinalli's Emergency Medicine: Just
the
Facts. New York: McGraw-Hill, 2013. Print.
• Leung, Nelson. "Types of Renal Disease in Multiple
Myeloma." Types of Renal Disease in Multiple Myeloma. N.p.,
n.d. Web. 13 Sept. 2015.
<http://www.uptodate.com/contents/types-of-renal-diseasein-multiple-myeloma>.