It is time for our 2010 Animal Insides summer hiatus. While we are gone, the SHOWDOWN will continue. You can be sure that we will be recharging our batteries to bring you new content later this year and in 2011 as we are working on some very interesting new projects. Before we go, we would like to introduce you to our newest collaborators at SONOPATH (www.sonopath.com). The folks over at SONOPATH have a monthly newsletter that you can sign up for to get your newsletter fix while we are gone. All you need to do is navigate over to SONOPATH and drop them a line to let them know you would like to be added to their mailing list. The following is a reprint of one of their recent case of the month newsletters. NOTE: the video clips for this case are over on their website.
See you in the fall...Dr. Lindquist...take it away....
History: An 11-year-old FS Standard Poodle presented for depression and anorexia. The physical exam revealed mild palpable splenomegaly. Blood analysis revealed a moderate neutrophilia (43,000 WBC) with a left shift. Blood chemistry was normal.
Clinical Differential Diagnosis (Lobetti BVSc, MMedVet, PhD, DECVIM):
Depression/anorexia - non-specific
Splenomegaly - neoplasia/torsion/infarction/primary splenic
infection/systemic infection/inflammation
Neutrophilia - infection/inflammation/neoplasia/immune-mediated disease
Sonographic Interpretation (Lindquist DMV, DABVP):
- Sonogram 1: Severely mottled echotexture with multifocal hypoechoic changes and several discrete complex hypoechoic nodules throughout. The overall splenic shape is irregular with capsular deviation suggestive for an aggressive pathological process.
- Sonogram 2: The largest discrete nodule is measured as a benchmark for future rechecks to assess any progression of the pathological process.
- Sonogram 3: VIDEO LINK HERE: Video clip assessment of the spleen better defines the diffuse nodular changes and scalloping capsular contour suggestive of a relatively aggressive underlying pathology.
- Sonogram 4: VIDEO LINK HERE: Further video clip assessment of an exemplary nodule in the spleen. Note the loss of architectural detail in that the curvilinear aspects of normal splenic parenchyma are completely lost owing to the underlying pathology. Sonogram 5: Color flow Doppler assessment of the splenic vasculature is adequately curvilinear yet without significant impingement from adjacent nodular changes. This is interesting in that usually, in my experience, neoplastic nodular changes are usually expansive within the architecture of the affected organ such as the capsule in this case. But this also usually includes deviation of vessels within the organ itself creating mini “mass effects” within the organ examined. This is not the case in this patient as the vessels maintain their normal straight contour within the spleen. Infiltrative disease (lymphoma, hemangiosarcoma, mast cell neoplasia….) is, of course, in the primary differential list given the parenchymal architectural deviation and scalloping splenic capsule. However, given the maintained linearity of the vasculature evidenced in color flow Doppler, an aggressive inflammatory or severe nodular hyperplasia pathology is to be considered as well.
Sonographic Differential Diagnosis (Henderson DVM):
Splenomegaly Diffuse
a) Inflammation (Splenitis)
1. Suppurative
2. Necrotizing
3. Eosinophilic
4. Lymphoplasmacytic
5. Granulomatous
6. Pyogranulomatous
b) Hyperplasia
1. Infection
2. Immune-mediated disease
3. Congestion
c) Infiltration
1. Neoplasia
2. Extramedullary hematopoiesis
3. Amyloidosis
Sampling: US-guided fine needle aspiration (Henderson DVM).
Cytological Interpretation (Barton DVM, DACVIM-Oncology/Internal Medicine):
Spleen - Moderate to marked extramedullary hematopoiesis, with focal pyogranulomatous inflammation suggestive of microabscesses; no evidence of lymphoma or other neoplastic infiltrate.
Comments from Dr. Barton: I suspect that the dog has been septic and that this is a suppurative splenitis superimposed on a spleen that was already mildly enlarged due to
extramedullary hematopoiesis (which would be a normal finding in an older dog). If there is no timely response to empirical antibiotic treatment, perhaps splenectomy will need to be considered. I would want to consider endocarditis as a source of bacteremia. Severe dental disease should also be considered. This could be a source of infection. Despite the fact that the dog has sonographically normal kidneys, one would want a urine culture. If intermittent fever is present, blood cultures would be appropriate, especially if the dog is not yet receiving antibiotics.
Outcome: The patient underwent splenectomy and long-term antibiotic therapy and recovered uneventfully. No cultures were performed owing to cost concerns.
Special thanks to: Marty Henderson DVM of Sonovet Inc (www.Sonovet.US,) San Antonio, Texas, USA for submitting this case.