Hemophagocytic lymphohistiocytosis secondary to progressive disseminated histoplasmosis presenting as cellulitis

Mimickers of erysipelas and cellulitis: A narrative review

A diffuse erythematous, edematous tender swelling with a distinct border and local rise in temperature suggest a morphological diagnosis of erysipelas-like eruption. While cellulitis and pseudocellulitis have an ill defined tender erythematous plaque. Erysipelas, and cellulitis are not a straightforward diagnosis as multiple cutaneous eruptions mimic erysipelas. It is important to have comprehensive knowledge about the different causes of erysipelas-like eruptions and pseudocellulitis to reach a diagnosis and treat appropriately. Many infectious diseases such as histoplasmosis, leishmaniasis, dermatophytosis, and infusion of chemotherapeutic agents result in erysipelas-like eruptions and pseudocellulitis. Malignancy-related dermatoses such as carcinoma erysipeloides, erysipeloides melanomatosum, and inflammatory dermatoses such as sweet syndrome, well syndrome, and Crohn's disease present as erysipelas-like eruption.

Pathophysiology and clinical outcomes of pancytopenia in disseminated histoplasmosis: a scoping review

PURPOSE

Pancytopenia in the setting of disseminated histoplasmosis is sparsely described in the literature. We investigated the underlying mechanisms of pancytopenia in disseminated histoplasmosis and highlighted clinical outcomes.

METHODS

We conducted a scoping review of cases and series on disseminated histoplasmosis presenting with pancytopenia published between 2001 and 2024. PubMed database was used for the search. The search terms were (disseminated histoplasmosis) AND (pancytopenia OR haemophagocytic syndrome OR lymphohistiocytosis).

RESULTS

We identified 72 cases. Forty-four (61.1%) cases were from the Americas, 18 (25.5%) from Asia, 8 (11.1%) from Europe, and 1(1.4%) each from Africa and Australia. Of the 72 cases, five cases (6.9%) were reported in children. The mean age was 41.9 ± 16.7 years with a range of 3 months to 78 years. Seven cases (9.7%) were immunocompetent, 27 (37.5%) had an underlying HIV infection and 45 (62.5%) were complicated with haemophagocytic lymphohistiocytosis syndrome. Histoplasma antigen assay (n = 29, 40.2%) was the major diagnostic method followed by bone marrow biopsy (n = 28, 38.9%). Fifty-three cases (73.6%) recovered, 15 (20.8%) died and outcomes were not stated in 4 cases (5.65%). The relationship between haemophagocytic lymphohistiocytosis and fatal outcomes was not statistically significant (P = 0.5). Likewise, HIV infection was not significantly associated with fatal outcomes (P = 0.6). Fatal outcomes were predominantly due to difficulty or delayed diagnosis of disseminated histoplasmosis and/or haemophagocytic lymphohistiocytosis (n = 5, 6.9%), multiple organ failure (n = 4, 5.6%) and late presentation (n = 2, 2.8%).

CONCLUSION

Pancytopenia in disseminated histoplasmosis is associated with poor outcomes. Such a hematologic finding should arouse the index of suspicion in the attending clinician for an invasive mycosis like disseminated histoplasmosis to avert fatal outcomes. Besides haemophagocytic lymphohistiocytosis, other factors associated with pancytopenia in disseminated histoplasmosis were the cooccurrence of viral and bacterial infections.

Fungal-Induced Hemophagocytic Lymphohistiocytosis: A Literature Review in Non-HIV Populations

We performed a thorough search of the literature published through December 2024 with no date exclusions on invasive fungal infection (IFI)-induced hemophagocytic lymphohistiocytosis (HLH) in non-human immunodeficiency virus (HIV) patients. The frequency of IFI-induced HLH reported across 16 articles was 9%. Of the 116 identified cases with available clinical information, 53% occurred in immunocompromised patients. IFIs were usually disseminated (76%), with Histoplasma capsulatum being the most common pathogen (51%). IFI and HLH were diagnosed simultaneously in most cases (78%). The 30-day survival rate was 64%. Reported cases had significant heterogeneity in patient characteristics, management strategies, and outcomes.