Diagnosis and Treatment of Chronic Skin Infection Caused by Scedosporium apiospermum

Summary

This case report presents a rare skin infection caused by Scedosporium apiospermum in an immunosuppressed patient that was successfully diagnosed using next-generation sequencing and treated with surgical debridement and voriconazole.

Abstract

This case report presents a 77-year-old male with purplish-red, blister-like lesions on the right forearm. A background of long-term corticosteroid therapy for pemphigus led to significant immunosuppression. Initial laboratory investigations, including bacterial and fungal cultures as well as histopathological analysis, yielded inconclusive results. To identify the causative pathogen, next-generation sequencing (NGS) was performed on tissue samples, which confirmed the presence of Scedosporium apiospermum, a rare opportunistic fungus. Based on this result, a targeted treatment strategy was implemented, involving multiple surgical debridements and systemic antifungal therapy with voriconazole. The therapeutic response was favorable, with complete resolution of the infection and no signs of recurrence during an 8-month follow-up period. This case highlights the clinical value of NGS in diagnosing rare and atypical infections, particularly in immunocompromised settings where conventional methods may fail. It also underscores the importance of a multidisciplinary treatment approach that integrates timely surgical intervention with appropriate antifungal therapy to achieve optimal patient outcomes.

Introduction

Skin and soft tissue infections (SSTIs) are among the most frequently encountered conditions in clinical practice, leading to repeated outpatient visits, prolonged hospitalizations, long-term disability, and even mortality. The incidence of SSTIs continues to rise annually, with severe cases often requiring a combination of aggressive surgical intervention and broad-spectrum antimicrobial therapy¹.

Although dozens of pathogens may be involved in SSTIs, bacterial infections remain the most common. However, in recent years, the increasing prevalence of geriatric comorbidities and widespread use of immunosuppressive the....

Protocol

The surgical procedure was approved and conducted per the hospital's ethical committee guidelines.Informed consent was obtained from all individual participants included in the study.

1. Initial evaluation and sample collection

1. Perform a comprehensive inspection of the affected skin, focusing on signs of erythema, swelling, ulceration, necrosis, and purulent discharge.
   NOTE: Record baseline visual assessment (photos, dimensions) and document initial clinical signs (erythema, edema).
2. Record a complete medical history, including the use of immunosuppressive agents (e.g., corticosteroids, chemo....

Results

A 77-year-old male with a history of pemphigus under long-term methylprednisolone therapy presented with progressive skin lesions on his right forearm. Initial evaluation, including physical examination (Figure 1) and MRI (Figure 2), revealed two ulcerated lesions with surrounding tissue edema and suspected deep soft tissue infection. Routine exudate culture detected Scedosporium apiospermum, but this was initially regarded as environmental contaminatio.......

Discussion

Skin is frequently exposed to pathogens, including bacteria, fungi, viruses, rickettsia, and parasites, with Staphylococcus aureus and β-haemolytic streptococci remaining the predominant causes of infection⁵. In recent decades, fungal skin infections have increased significantly, with mortality rates exceeding 50% among susceptible populations⁶. Scedosporium apiospermum, in particular, is recognized as a significant human fungal pathogen

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Bipolar electrocautery	BAISHENG	20173251560
Ceftriaxone	Roche	H10983036
CLC Genomics Workbench	Qiagen	v23.0	Data analysis and visualizaion software
Corticosteroids	Pfizer	Hj20170197
DNeasy Blood & Tissue Kit	Qiagen	https://www.qiagen.com/us/products/discovery -and-translational-research/dna -rna-purification/dna-purification /genomic-dna/dneasy-blood-and -tissue-kit
Labeled containers	3L	N/A
MiSeq	Illumina	https://www.illumina.com/systems/ sequencing-platforms/miseq.html	NGS
MiSeq Control Software	Illumina	https://www.illumina.com/systems/ sequencing-platforms/miseq.html
MiSeq Reagent Kit v3	Illumina	https://www.illumina.com/products/ by-type/sequencing-kits/cluster-gen -sequencing-reagents/miseq- reagent-kit-v3.html
MRI	SIEMENS	3146466
Nextera XT DNA Library Prep Kit	Illumina	https://www.illumina.com/products /by-type/sequencing-kits/library- prep-kits/nextera-xt-dna.html	DNA Library Prep Kit
QIAamp DNA Mini Kit	Qiagen	51304	DNA extraction kit
Qubit dsDNA HS Assay Kit	Thermo Fisher Scientific	https://www.thermofisher.com/in/en /home/industrial/spectroscopy- elemental-isotope-analysis/ molecular-spectroscopy/fluorometers /qubit/qubit-assays.html?ef_id=: G:s&s_kwcid=AL!3652!10!775157 26968096!!!!77515743318006!!3 80468453!1240249321530142& cid=bid_pca_aqb_r01_co_cp1359_pj t0000_bid00000_0se_bng_bt_pur_con
Scalpel	JZ	20140019
Sterile swab	Meidike Gene	MWS001
Voriconazole	Pfizer	H20150168