1. HypercalcaemiaHypercalcaemia
The Hunt for the TumourThe Hunt for the Tumour

2. 10 year old MN Labrador Cross
Presented at the SAH on 23/09/13
for further investigation of PU/PD
Past 3 months showing signs of:
PU/PD
Lethargy
Weight loss
Anorexia
Weakness
Yellow DogYellow Dog

3. HistoryHistory
First visit to vets on 09/08/13
Biochemistry:
Calcium 3.83 mmol/l
No other abnormalities
Urinalysis:
USG 1.010 (Isosthenuric)
pH 7
No other abnormalities
Second visit to vets on 19/08/13
Water deprivation test:
7am: USG 1.0095, weight 33.4kg
12pm: USG 1.009, weight 33.15kg
2pm: USG 1.012, weight 32.8kg
4pm: USG unable to get urine, weight 31.7kg

4. HistoryHistory
• Results of the water deprivation test indicative of Diabetes Insipidus.
• Started on Desmopressin 0.1mg 1.5 tablets SID
• Retested urine on 27/08/13
• USG 1.010
• Drinking less, urinating the same but doing “bit poorly” per owner
• Changed Desmopressin to 2 tablets SID
• Retested urine on 09/09/13
• USG 1.011
• Drinking less, urinating the same, not interested in food, very thin, lethargic
• Retested urine on 16/09/13
• USG 1.010
• Still unable to concentrate urine, not eating, lethargic, muscle weakness

5. Physical ExaminationPhysical Examination
Quiet, alert and responsive
Thoracic auscultation and abdominal palpation
were unremarkable
No evidence of any anal gland masses on rectal
exam
Peripheral lymph nodes were unremarkable
BCS 2/5 and weighed 30.2kg

6. HaematologyHaematology
Mild Leukocytosis and
left shift
The left shift is extremely
mild and probably not
significant.

7. BiochemistryBiochemistry
Marked Total Hypercalcaemia (4.24
mmol/l)
Hypophosphataemia
Hypercholesterolaemia
Ionised Calcium: 2.17 mmol/l
consistent with
HYPERCALCAEMIA!!

8. UrinalysisUrinalysis
USG 1.014
pH 6
Normal UPC ratio
0.04

9. HypercalcaemiaHypercalcaemia
H: hyperparathyroidism
A: addison’s disease; vitamin A toxicosis
R: renal disease
D: vitamin D toxicosis, dehydration
I: idiopathic
O: osteolytic (multiple myeloma)
N: neoplasia (anal sac adenocarcinoma, lymphoma)
S: spurious (lab error, lipemic sample causing false
elevation of calcium)

10. Thoracic RadiographsThoracic Radiographs
Increased soft tissue
opacity in cranial thorax,
with splaying of the
cranial lung lobes and
elevation of the trachea
Loss of clarity of cranial
cardiac silhouette
Cranial Mediastinal
Mass (ie. LSA, thymic
lymphoma)
Possible bony lesions
affecting sternebrae 4 &
5 and the dorsal spinous
processes of T4 and T9
Mediastinal
Mass

11. Abdominal UltrasoundAbdominal Ultrasound
Spleen diffusely mildly mottled
(consistent of nodular hyperplasia,
extramedullary haematopoises,
reactive splenitis, congestion or
infiltrative neoplasia).
Gall bladder mild wall thickening
(consistent with previous or
chronic cholecystitis).
Both kidneys cortices were
diffusely bright and pelvis
deverticuli were associated with
mineralisations (consistent with
age related changes or chronic
renal disease).

12. Thoracic UltrasoundThoracic Ultrasound
In the cranial thoracic cavity cranial to the heart,
there was a large heterogeneous mass.
Two round large hypoechoic slightly
heterogeneous masses were identified as enlarged
cranial mediastinal lymph nodes.
Ultrasound guided FNA of both mediastinal mass
and lymph node: sadly non-diagnostic.

13. PCRPCR
• FNA was submitted for PCR to enable us to see
if a monoclonal population of lymphoid cells are
present which would be consistent with
lymphoma.
• Results:
• Polyclonal distribution suggesting presence
of a mixed population of T-Cells.

14. DiagnosisDiagnosis
Suspect T-cell Mediastinal Lymphoma
• Stage V substage b Lymphoma
Why was it suspect stage
V?Could there be any other
possible causes?

15. Hypercalcaemia of MalignancyHypercalcaemia of Malignancy
• Hypercalcaemia is a paraneoplastic syndrome in domestic animals and is a great
tumour marker.
• The 2 most common non-parathyroid neoplasms that cause persistent hypercalcaemia
in dogs:
• Lymphoma (Lymphosarcoma)
• Adenocarcinoma of the apocrine glands of the anal sac
• Hypercalcemia of malignancy manifests as a result of three underlying pathological
processes associated with neoplasia:
• interference with 1 alpha-hydroxylase activity, leading to unregulated conversion of
calcidiol to active calcitriol and enhanced intestinal absorption of calcium
• hypersecretion of parathyroid releasing protein (PTHrP), a polypeptide structurally
similar to intact parathyroid hormone
• heightened activity of interleukin-1, interleukin-6 and tumor necrosis factor. The
production and secretion of these humoral mediators lead to pathologic increases in
osteoclastic resorption, often without visible radiographic bone lesions.

16. TreatmentTreatment
Fluid therapy with 0.9% NaCl
• providing additional sodium to renal tubules will diminish calcium reabsorption and
increase calciuresis
Diuretics following rehydration
• furosemide will increase calcium excretion by the kidneys
Glucocorticoids
• dexamethasone reduce bone resorption of calcium, reduce intestinal calcium absorption,
and increase renal calcium excretion
Calcitonin
• rapid calcium-lowering effect due to inhibitory effects on osteoclastic activity and renal
tubular reabsorption of calcium.
Bisphosphonates
• act to lower serum calcium by reducing the number and action of osteoclasts

17. PlanPlan
Further investigation was discussed with the owner
to be able to obtain a definitive diagnosis but this
was declined.
Owners would like to trial palliative steroids. This
will help reduce his hypercalcaemia and improve his
appetite.
Prednisolone 25mg tablets and Zantac 150mg
tablets.
Owners want to take him home for a few days and
then euthanise.

18. The EndThe End