Prevalence and diagnostic value of the ultrasonographic honeycomb appearance of the spleen in cats

Abstract

Objectives The aim of this study was to report the prevalence of a honeycomb appearance of the spleen in a population of referral cats presented for ultrasound examination, and to determine the diagnostic value of this finding vs the definitive diagnosis, the splenic cytological and haematological results. Methods Data were obtained from the medical records (2016–2018) of cats that had an ultrasonographic honeycomb appearance of the spleen, a splenic cytological diagnosis and a complete blood count. Results Twenty-five cats were included. Prevalence of the honeycomb pattern was 6.8%. None of the spleen was considered normal on cytology and four types of lesions were found: lymphoid hyperplasia (64%), neoplasia (16%), extramedullary haematopoiesis (12%) and splenitis (8%). A honeycomb pattern was successfully identified with a linear high-frequency probe in all cats, but only in 36% of cases with the micro-convex probe. Follow-up information was available for four cats, in which the honeycomb appearance persisted up to 105 days after the first examination; there was persistence of the honeycomb pattern in all cases. Cats with a splenic cytological diagnosis of extramedullary haematopoiesis had the lowest haemoglobin plasma concentration ( P = 0.011). Conclusions and relevance Honeycomb appearance of the spleen is uncommon in cats and, in our study, was systematically associated with cytological alterations; most of the time it was benign (84%). The use of a high-frequency linear probe improves its detection rate. No epidemiological, ultrasonographic or clinical criteria allow differentiation between the different types of infiltration and fine-needle aspiration is therefore recommended.

Bidimensional and Contrast-Enhanced Ultrasonography of the Spleen in Dogs Affected by Leishmaniosis

“…Honeycomb, Swiss-cheese-like, and moth-eaten are the metaphorical names used to describe the ultrasonographic finding of small hypoechoic nodules throughout the spleen, causing a spotted echotexture that is commonly seen not only in lymphoma and mast cell neoplasia but also in benign conditions (extramedullary hematopoiesis, lymphoid hyperplasia, and pyogranulomatous splenitis) in dogs and cats [ 34 , 35 , 36 ]. These above-mentioned metaphorical definitions are, however, synonyms.…”

Ultrasonographic honeycomb pattern of the spleen in cats: correlation with pathological diagnosis in 33 cases

“…These findings are consistent with previous studies showing a lack of agreement between a US diffusely inhomogeneous appearance of the spleen and a cytological diagnosis of malignant neoplasia, and the frequent association of this US pattern with benign splenic lesions in cats. 6,9,12 Therefore, when a US splenic HCP is observed in cats, multiple differential diagnoses should be considered, including benign lymphoproliferative, inflammatory and reactive diseases, although lymphoma is still a likely option.…”

“…2,4,5 Recently, two reports investigating the association between feline splenic US appearance and cytological diagnosis showed that diffuse inhomogeneity of the spleen with hypoechoic foci, described as moth-eaten or HCP, was not always related to neoplastic disorders. 6,9 The purpose of this study was to assess the correlation between a splenic HCP and the final cytological or histological diagnosis, and to determine the prevalence of lymphoma in cats with a splenic HCP. In addition, we aimed to establish whether the use of high-frequency linear transducers might increase HCP visualisation.…”

“…2,4,5 Recently, two reports investigating the association between feline splenic US appearance and cytological diagnosis showed that diffuse inhomogeneity of the spleen with hypoechoic foci, described as moth-eaten or HCP, was not always related to neoplastic disorders. 6,9…”

Feline abdominal ultrasonography: What’s normal? What’s abnormal? The spleen

“…14 Similarly, a further study involving 25 cats with a honeycomb splenic pattern identified neoplasia in only 16% of cases (of which 3/4 were lymphoma), with the remainder having lymphoid hyperplasia (64%), EMH (12%) or splenitis (8%). 15 Diffuse splenomegaly is also particularly common in cats with lymphoma ( Figure 7). In one study, 83% of cats with splenic lymphoma had an enlarged spleen and, in 32% of cases, enlargement was the only splenic change observed.…”