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Date of last update: 10/12/2017.

Forum Name: Hematology Topics

Question: Dilantin causing high RBC in Urine?

 shergeune - Mon Jan 09, 2006 8:15 pm

Thank youf or taking the time to read my post. I am a 26 year old man, 150 lbs., 5'10". I am currently on Dilantin for epilepsy. I take 400 mg on even days, 500 mg on odd days. I was recently declined life insurance due to a high level on an "RBC Micro Exam" test. Here are my urinalysis results:

Test Name
Glucose quantitative 0.01 gm%
Gcast Micro Exam 0/40 LPF
Hcast Micro Exam 0
RBC Micro Exam 214 HPF
WBC Micro Exam 1/HPF
Cotinine NEG
Protein 15
Urine Temp. 95.0 F
Adult Creatinine 224.0 mg/dl
Adulterant PH 5.7

Is this RBC result something that I should be really worried about, or likely a result of Dilantin at work? Any information would be greatly appreciated.

Thank you.
 R. Zein, Pharm D - Mon Jan 23, 2006 10:50 am

User avatar Hello

based on the numbers you have provided, you have microscopic Hematuria , which is presence of red blood cells in urine

there are in general many different causes of it:

1) Pre-Renal :Coagulopathies - TTP, Hemophilia , Wilm's Tumor ,
Sickle Cell Disease,Collagen Vascular Disease, and Vasculitis

2) Renal :
Nonglomerular: Pyelonephritis , AVMs,Neoplasms,Tuberculosis , Polycystic Kidney
and Glomerular: Alport's Syndrome, Berger's Disease, Lupus nephritis, Benign familial hematuria , AVMs , Vasculitits , glomerulonephritis

3) Post Renal

Renal Stones, , neoplasms , Uretrhritis , Cystitis ,BPH/prostatitis

Additional possible causes are :
False Positives:
Vaginal bleeding
Foods - beets, black berries, fava beens, rhubarb

and importantly especially in your case:

Medications - quinidine, dilantin, rifamipin, sulfasalazine, phenanzopyridine, phenothiazine

Physiologic Causes - Exercise, fever, trauma

so as i mentioned above, dilantin can cause false positive microscopic hematuria, however, if this symptom continues to bother you, or if you have any additional concerns, you may discuss it with your doctor,

if the positive RBC test in your urine turn out to be false positive, your doctor may want to persue some work up modalities: which can include the following:

Renal Ultrasound
Sickle Cell testing - including r/o sickle cell trait
24hour urine for uric acid and calcium
Urine cytology - to evaluate for transitional cell CA
Sedimentation Rate
Coagulation testing

thank you very much and i hope you always feel better.

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