Histologic features of granulomatous skin diseases

[Facial manifestations of granulomatous diseases]

Clinical manifestations of granulomatous diseases are a recurring challenge in everyday dermatological practice. Clinical presentation and histological patterns are variable, depending on the particular disease. Knowledge about the differential diagnosis of granulomatous changes in the face is of decisive importance for making a rational diagnosis and therapy considering the patient's well-being. Therefore, histological and clinical characteristics of important granulomatous diseases that typically manifest on the face are presented here.

[Differential diagnosis of granulomatous diseases]

Despite advances in the understanding of the pathophysiology, granulomatous diseases remain a diagnostic challenge for the clinician as well as for the pathologist. However, establishing the correct diagnosis of these diseases is a crucial prerequisite of targeted therapy. It is particularly essential to distinguish between an infectious and a non-infectious cause, since anti-infectious and anti-inflammatory or immunosuppressive approaches are opposing. Failure to establish the correct diagnosis can lead to adverse consequences for the patient. An interdisciplinary approach and a critical assessment of clinical, laboratory-chemical, microbiological, imaging, and anatomical-pathological findings are crucial for the evaluation of granulomatous disorders. This overview summarizes important landmarks and their value in the interplay of arriving at the correct diagnosis.

Paracoccidioidomycosis with sarcoid-like lesions:a diagnostic challenge

Clinical presentation of paracoccidioidomycosis (PCM) can be diverse. Morphology and quantity of skin lesions depends on interactions between host immunity and fungus virulence. Diagnosis can be a challenge considering that this fungus has low virulence and some individuals have immunity to microorganism, which results in well-marked granulomas without visible microorganisms. We report herein a clinical presentation of sarcoid-like PCM, initially diagnosed as tuberculoid leprosy. This rare type of PCM is often mistaken for other types of chronic granulomatous diseases. Diagnosis was confirmed after 4 years when a special stain analysis helped in the identification of the specific etiologic agent.