Question 13.3

The following blood tests are from an otherwise well 53-year-old female, admitted to a general medical ward five days previously for intravenous antibiotic therapy for lower limb cellulitis. Her admission blood tests were all normal. Over the last 24 hours she has become progressively oliguric, but remains otherwise stable with normal vital signs.

The results of her full blood count and urea and electrolytes are as follows:

Parameter	Patient Value	Normal Adult Range
Haemoglobin	132 g/L	130 - 175
White Cell Count	9.8 x 109/L	4.0 - 11.0
Platelets	321 x 109/L	150 - 450
Neutrophils	10.4 x 109/L*	1.8 - 7.5
Lymphocytes	2.06 x 109/L	1.50 - 4.00
Monocytes	0.3 x 109/L	0.2 - 0.8
Eosinophils	4.3 x 109/L*	0.0 - 0.4
Haematocrit	0.35*	0.40 - 0.52
Mean Cell Volume	92 fl	82 - 98
Mean Cell Haemoglobin	29.9 oa/cell	27.0 - 34.0
Mean Cell Haemoglobin Concentration	326 g/L	310 - 360

Sodium	140 mmol/L	135 - 145
Potassium	3.8 mmol/L	3.2 - 4.5
Chloride	106 mmol/L	100 - 110
Bicarbonate	22 mmol/L	22 - 27
Urea	28.0 mmol/L*	3.0 - 8.0
Creatinine	310 µmol/L*	45 - 90
Total Calcium	2.17 mmol/L	2.15 - 2.60
Phosphate	1.6 mmol/L*	0.7 - 1.4
Albumin	31 g/L*	33 - 47
Total Bilirubin	20 umol/L	4 - 20
Conjugated Bilirubin	4 µmol/L	1 - 4
y-Glutamvl transferase	22 U/L	0 - 50
Alkaline phosphatase	60 U/L	40 - 110
Lactate dehydrogenase	213 U/L	110 - 250
Aspartate transaminase	34 U/L	< 40
Alanine aminotransferase	25 U/L	< 40

Give the likeliest cause of her oliguria. (20% marks)

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College answer

Allergic / Acute Interstitial nephritis secondary to antibiotic use.

Discussion

The eosinophils. They are high.

Everything else is normal.

It could be nothing else. The cellulitis, presumably it got flucloxacillin - and then the cillin caused an interstitial nephritis, as they tend to do.

References

Perazella, Mark A., and Glen S. Markowitz. "Drug-induced acute interstitial nephritis." Nature Reviews Nephrology 6.8 (2010): 461-470.

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