Case Study: Dark Urine after Strep Throat
A 3-year-old male was diagnosed with strep throat and prescribed to take
penicillin to treat the disease. His mother is also a believer in
curative treatment, so she made sure her son took three vitamins
everyday in addition to the penicillin. However, one week later,
his mother noticed that he had dark brown urine which persisted for
days and was urinating less frequently than usual. When she took her son to the physician, a routine
urinalysis was performed and the results were as follows:
Color:
Amber
Protein (mg/dL):
Small
Blood: Small
Appearance: Hazy
Glucose:
Negative
Urobilinogen (mg/dL): 0.2
Specific
Gravity: 1.012
Ketones:
Negative
Nitrite: Negative
pH:
5.0
Bilirubin:
Negative
Leukocytes: Moderate
Microscopic
50-100 RBC/hpf
20-50 WBC/hpf
2-5 RBC casts/hpf
10-20 Squamous Epithelial Cells
0-2 Renal Epithelial Cells
Calcium Oxalate crystals
Reference Ranges
1.
What is the major discrepancy between the microscopic and chemical
results? What is the cause of the discrepancy?
Answer
2.
In general, what other chemical tests can be affected by the cause of
the discrepancy in question 1? HINT: The discrepancy is not
present in this case for any chemical tests other than blood.
Answer
3. What type of cell is shown below? Is it indicative of the disease that is causing the dark urine?
Answer
x400
4.
Does the presence of the crystals shown below correlate with the
results of the routine urinalysis? If so, what conditions are
needed for the crystals to form?
Answer
x400
5. What is the probable diagnosis for this patient?
Answer
Case Study 1
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