Panniculitides comprise a group of heterogeneous inflammatory diseases. Nevertheless, histopathological study along with clinicopathological correlation usually led to a specific diagnosis. In most textbooks, the first step in the diagnosis is to classify them as mostly septal or lobular depending on where the inflammatory infiltrate is located. The second step is deciding if vasculitis is present or not. Finally, the third step is further characterizing the inflammatory infiltrate. However, in addition to the algorithmic approach to panniculitis diagnosis, some subtle changes may help to the diagnosis.
To review some clues in panniculitis dermatopathological diagnosis such as presence of granulation tissue, sclerotic connective tissue septa, small granulomas arranged around a central clear space, so-called ghost adipocytes, needle-shaped crystals, small lobules with a proliferation of capillaries, Splendore-Hoeppli phenomenon, refractile microspheres, neutrophilic infiltrates, granulomas and fibroplasia or presence of adipose tissue in dermis.
We have compiled 12 clues based in our personal experience in this field.
Specificity and sensibility of every clue may vary and these clues are a guide to correct diagnoses that should rely in clinicopathological correlation.
Knowledge of these 12 clues will help to increase the diagnostic accuracy in panniculitis diagnosis.
*Dermatology Faculty, Department of Dermatology, Hospital Universitario de La Princesa, Madrid, Spain;
†Pathology Faculty, Department of Pathology, Fundación Jiménez Diaz, Madrid, Spain;
‡Head of Dermatopathology Department, Kempf und Pfaltz Histologische Diagnostik, Zurich, Switzerland;
§Dermatopathology Faculty, Dermatopathologie Bodensee, Friedrichshafen, Germany;
¶Head of Dermatopathology, Dermatopathology Research Unit, Medical University of Graz, Graz, Austria; and
‖Head of Surgical Pathology, Pathology Department, Hospital Univeristari General de Catalunya, Sant Cugat del Vallés, Barcelona, Spain.
Correspondence: Mar Llamas Velasco, PhD, C/Diego de León 62, CP 28006, Madrid, Spain (e-mail: firstname.lastname@example.org).
All authors and staff in a position to control the content of this CME activity and their spouses/life partners (if any) have disclosed that they have no financial relationships with, or financial interests in, any commercial organizations pertaining to this educational activity.