every 24 hours( Loxicom, Norbrook, 0.5 mg / ml) to continue at home, with a presumptive diagnosis of suspected soft tissue injury. The owner reported that the right hindlimb lameness reduced following the first 2 days of treatment but then significantly worsened immediately after this. Sybil returned to toe-touching lameness on the right hindlimb, and swelling, predominantly over the thigh and stifle, was evident. On day 5, due to the poor response to analgesia and progression of clinical signs, Sybil was sedated to facilitate further examination of the hindlimb and radiography.
Radiographs were challenging to obtain due to the inability to extend the hindlimbs, even under sedation. Radiographs confirmed marked soft tissue swelling but no other concerns.
No bruising or petechiae were present and there was no evidence of any wounds or abscesses. Differential diagnoses at this stage were cellulitis and deep soft tissue injury, and Sybil was prescribed a number of medications( Table 1).
Table 1. Medication prescribed on day 5.
Drug
Buprenorphine( Vetergesic, Ceva Animal Health, 0.3 mg / ml)
Co-amoxiclav( Clavaseptin, Vetoquinol, 50 mg)
Meloxicam( Loxicom, Norbrook, 0.5 mg / ml)
Dosage
0.02 mg / kg orally every 8 hours
12.5 mg / kg orally every 12 hours for 7 days
0.05 mg / kg orally every 24 hours
Following treatment, Sybil remained painful in the quadriceps region, and the right hindlimb progressed from lameness to rigid extension, with toe-touching lameness on her left hindlimb( Figure 1). Her extremities remained warm, and both femoral and metatarsal pulses were strong and palpable.
On day 12, due to the rapid and severe deterioration in the mobility of Sybil ' s hindlimbs, the decision was made to refer her to a referral practice for further diagnostic investigation in the form of a contrast computed tomography scan. A fluid-filled lesion was found extending over the cranial aspect of the quadriceps. Enlargement of the medial iliac and inguinal lymph nodes was also noted. Fine-needle aspiration samples were taken from these regions and sent for cytology and culture. Sybil was discharged and continued on meloxicam 0.05 mg / kg orally every 24 hours with additional gabapentin 6 mg / kg orally every 8 hours( Gabapentin, Summit Pharmaceuticals, 25 mg) while waiting for the laboratory results.
Figure 1. The patient, with the hindlimbs in rigid extension.
On day 14, the cytology showed marked neutrophilic inflammation and culture was negative. At this stage, the primary differential diagnoses were tissue trauma and / or a tracking foreign body or myositis caused by secondary infection with a pathogen such as Toxoplasma or Clostridium( the causative agent of tetanus).
Treatment
On returning home, Sybil showed marked deterioration daily, with extension of the right hindlimb spreading to the left hindlimb and a pain score of 13 / 20 on the Glasgow Feline Composite Measure Pain Scale [ 6 ]. On day 14, the decision was made to readmit her to the referral practice for analgesia and intravenous( IV) antibiotics.
Blood tests showed mildly elevated aspartate aminotransferase and high creatine kinase, as well as some other biochemical and haematological values outside their normal ranges( Table 2).
Table 2. Biochemistry and haematology results outside the normal ranges.
Test Result Normal range
Aspartate aminotransferase
72 U / l 0 – 48 U / l
Creatine kinase 1046 U / l 0 – 314 U / l Lactate 3.95 mmol / l 0.60 – 2.50 mmol / l Chloride 111 mmol / l 112 – 129 mmol / l
White blood cells 21.36 × 10 9 / l
Neutrophils 18.78 × 10 9 / l
Eosinophils 0.06 × 10 9 / l
2.87 – 17.02 × 10 9 / l
2.30 – 10.29 × 10 9 l
0.17 – 1.57 × 10 9 / l
12 Veterinary Nursing Journal