May 10 Case of the Month: Dog with anorexia & vomiting

Re: May 10 Case of the Month: Dog with anorexia & vomiting

Ian Battersby — Thu, 03 Jun 2010 11:17:23 GMT

The biggest concern in these patients is that the other parathyroid’s atrophy. So when you remove the abnormal gland your patient becomes hypoparathyroid and at risk of hypocalcemia. This most commonly occurs within 5 days of surgery but is reported up to 20 days post surgery. So close monitoring of calcium is very important. Minimizing exercise in this period can reduce the chances of a hypocalceamic crisis whilst keeping an eye on the calcium.

This is the dogs parathyroid during surgery.

www.vetsurgeon.org/.../5543.Doc9.doc

So generally in these cases the surgery is the easy bit ( don’t tell the surgeons that) and it is the post operative monitoring and treatment that is the most challenging.

Certainly Vitamin D prophylaxis is an option and in patient with a marked hypercalcemia (Total calcium >3.7mmol/l ( 2-3mmol;/l) atrophy of the other glands is likely . So it is my preference to start vitamin D therapy either the night before or the day of surgery. I normally use calcitriol as it has a quicker onset of action than the other preparation and if I have too high a dose it also wears off quicker.

Using vitamin D can have its problems in that in some cases the gland to remove is not obvious unlike this case or more than one PTH gland may be adenomatous and abnormal. So the surgeon takes an educated guess on which one is affected. In those cases if the calcium doesn’t come down the dilemma is whether it is your vitamin D therapy or you haven’t taken the right gland out

So this dog had surgery and vitamin D therapy. Recovery was good and the renal function recovered. The dog was slowly weaned off vitamin D over a 6 week period and hasn’t looked back

Re: May 10 Case of the Month: Dog with anorexia & vomiting

Ian Battersby — Wed, 02 Jun 2010 10:04:40 GMT

Points to Consider
The points I extrapolated from the bloods and radiographs were as follows:

We now have a bench mark for our azoteamia for monitoring
no hyperphosphoteamia is not consistent with hypervitaminosis
A hypophosphoteamia - is consistent with HPTH and potentially hypercalceamia of malignancy.
The haematology made a bone marrow malignancy less likely but didn't exclude it
Ionised Calcium elevated
No Na:K abnormalities makes addision very unlikely. Although could have been affected by fluids and
No hematological evidence of chronic inflammation - pretty much eliminating granulomatous disease
Radiographs show no evidence of changes consistent with angiostrongylus
Radiographs show no evidence of neoplastic disease.

So malignancy is still my top differential, although hyperparathyroidism although uncommon would be a possibility.

So my revised problem list is

Hypercalceamia - Malignancy most likely and HPTH second.
Azoteamia- secondary to dehydration and RF

My Diagnostics plan was
To perform an abdominal ultrasound. The abdominal scan was unremarkable . As you suggested did also scan the thyroid area. Below is a copy of the scan. It shows a large but not palpable nodule within the thyriod in the parathriod area. Following this I did submit a PTH assay whilst preparing the patient for surgery.

Treatment plan
I was concerned regarding the calcium so I did start frusemide once I was happy the dog was well hydrated.and still on high rate fluids.

Monitoring plan
Continued with the electrolyte and calcium monitoring and supplemented the potassium as appropriate

Re: May 10 Case of the Month: Dog with anorexia & vomiting

Hannah Wynne Richards — Thu, 27 May 2010 17:29:58 GMT

I've been treating these cases as exam questions-not cheating by looking anything up-so have to admit I'm now stuck Ca is climbing rapidly in spite of fluids. This, and the dogs body condition, suggest something acute. I would be looking at persuading the owner to refer at this point

I'll follow the rest of the discussion with interest

Wynne

Re: May 10 Case of the Month: Dog with anorexia & vomiting

Ian Battersby — Thu, 27 May 2010 09:33:55 GMT

Plan

Treatment – certainly priority is to reduce the calcium. This will hopefully improve the dogs demeanour but most importantly try and reduce the effects of the calcium on the kidneys. The sooner the calcium is reduced, the better odds we have of making any renal failure reversible. It is possible that the azotemia is a summation of dehydration and renal failure.

So I started the dog on - Intravenous Normal Saline (4xmaintanance 8mls/kg/hr). Normal saline contains no calcium, the high rate and the sodium with assist diuresis of the calcium. Frusemide would be my second choice as it increases calcium excretion but it is important to ensure your patient is well hydrated before starting this therapy. I would Calcitonin is an option or intravenous bisphosphonates ( like pamidronate) . I have never used caclitonin. I have tried using bisphosphates orally but find them ineffective if given orally due to their poor bioavailability.

Steroids can reduce blood calcium levels but I would not use them until I have made a diagnosis as they will affect diagnostics e.g. a lymphoma could respond to them.

Investigations

1. Obtain Minimum Database- Biochemistry, Heamatology and urinalysis. The biochemistry profile will enable me to assess the degree of azotemia as the prior information is sparse. But also the profile can assist us in tailoring our differentials further. In particular the blood phosphate which may help with our hypercalceamia differentials and other electrolytes such as Na and Potassium.

2. Survey Thoracic/abdominal radiographs – As neoplasia is very high on the list I felt it was justifiable starting routine screening. Thoracic and abdominal radiographs will allow us to screen for neoplasia screening for metastasis, LN enlargement etc.

Monitoring

Electrolytes to monitored daily- in particular calcium to ensure we are reducing its level. Potassium and if possible Magnesium. You can induce hypokalaemia and hypomagnesia with high rate of fluids.

I would also monitor the renal parameters to ensure the azotemia isn’t getting worse.

Nutrition

No immediate concerns. So no measure taken

Results

Biochemistry

Total Protein	65	g/l	54-77.0
Albumin	32.4	g/l	26.0 – 40.0
Globulin	32.6	g/l	20.0 -47.0
Sodium	154.9	mmol/l	139-154
Potassium	3.84	mmol/l	3.5 – 6.0
Chloride	112	mmol/l	99-112
Total Calcium	4.15	mmol/l	2.0-3.0
Phosphate	0.79	mmol/l	0.8-1.6
Urea	15.0	Umol/l	2.0-9.0
Creatinine	204	U/L	40.0-106.0
ALKP	45	U/L	0.0 – 25.0
ALT	56	U/L	0.0-49.0
AST	7	U/L	0.0 – 49.0
GGT	8	U/L	0-27.0
Total Bilirubin	3	Umol/l	0- 9.0
Glucose	4.9	mmol/l	2.0-5.5
CK	153	U/L	0.0-190.0
Cholesterol	7.2	mmol/l	3.8- 7.0
Amylase	587	U/L	0.0 – 1800.0
Lipase	26	U/L	0.0 – 250.0
Magnesium	0.6	mmol/l	0.6-1.3

RBC	5.46	x10¹²/l	5.0-8.5
Hb	13.30	g/dl	12.0-18.0
HCT	39.8	%	37.0-55.0
MCV	72.8	fl	60-80
MCH	24.4	pg	19.0-26.0
MCHC	33.6	g/dl	31.5-37.0
Platelets	221	x10 ⁹/l	160-500
WBC	14.2	x10 ⁹/l	6.0-15.0
Neutrophils	11.93	x10 ⁹/l	3.0-11.5
Lymphocytes	1.28	x10 ⁹/l	1.0-4.8
Monocytes	0.85	x10 ⁹/l	0-1.3
Eosinophils	0.14	x10 ⁹/l	0-1.25

RBC – normal morphology

Platelet count accurate

Urine

Ph	6.4
Blood	Negative
Glucose	Negative
Ketones	Negative
Protein	Negative
Sg	1.009
Urine Deposits	Scant Epithelia cells
Urine culture negative

Radiology Report

Thoracic and Abdominal Radiographs NAD

Re: May 10 Case of the Month: Dog with anorexia & vomiting

Ian Battersby — Mon, 24 May 2010 11:18:30 GMT

Problem List-

Hypercalceamia
Azoteamia
Vomiting

lethargy and anorexia - non specific signs likely secondary

Differential Diagnosis

Hypercalceamia

Hypercalceamia of malignancy- lymphoma, myeloma, apocrine adenocarcinoma

Primary Hyperparathyriodism

Hypoadrenocortism

Hypervitaminosis D

Chronic Renal Failure

Angiostrongylus

Chronic Inflammation e.g. Systemic Mycosis

Azoteamia

Pre Renal- Dehydration

Hypovoleamia

Hypoadrenocortism

Renal- Renal Failure

Post Renal- Obstruction

Vomiting

Gastric- Gastritis, Obstruction e.g. foreign body, Neoplasia, Ulceration

Intestinal- Obstruction,SIBO

Non Gastric-Hypoadrenocortism,Hypercalceamia,Renal Failure,Acid Basedisorders,Hepatobiliary Disorders

Although we have a number of problems hypercalceamia appears on all of our differential lists ( can cause vomiting and Renal failure). So I decided to priotise my diagnostics on this problem. It also has the shortest list of potential differentials.

Based on the history and clinical history, it was possible prioritise the differential list alittle by considering the following points.

1- The presence of hypercalceamia on the referring vets bloods before azoteamia developed, excluded renal failure as the primary cause of the hypercalceamia . As well as no history of PU/PD so CRF again would be unlikely). If I was concerned that RF may be the primary cause then an ionised calcium would be useful as compared with other causes of hypercalceamia ionised calcium is normal .

2- No response to glucocorticoids made addisons less likely – but doesn’t exclude it as some dogs in crisis need a few days to respond. Electrolyte status was unknown.

3- No response to glucocorticoids made neoplasia such as lymphoma less likely . However lymphoma is not excluded on this basis and if lymphoma is present this could make finding it very challenging . So I would suggest that steroids are not given to any patient with hypercalceamia until a diagnosis is established.

4- The dog was not a scavenger and there was no know access to poisons made hypervitaminosis D less likely but doesn’t exclude it Sources of vitamin D include rodenticides and psorasis cream. So always good to check no one has psorasis in the household

5- Granulomatous disease would seem unlikely as this is a relatively acute history. I would have expected signs of a other disease to have developed before the hypercalceamia.

Hypercalceamia of malignancy is the most common aetiology so would be top of my differentials. RF has been excluded. The information we have so far is diffinitive but a number of the other differentials would seem unlikely. Hard to comment on the aniostrongylus and HPTH from the information we have so far