dr. Parul sharma's MUCORM...

Mucormycosis Presenting as Intra-Thoracic Mass With Superior Vena Cava Obstruction In An Immunocompetant Patient- A Rare Case Report

INTRODUCTION:  
- Mucormycosis is an uncommon, invasive and fatal fungal infection of the order Mucorales.
- Usually affects patients with alteration in their immunological system. 
- Has recently emerged as an opportunistic mycosis in severely immunocompromised patients, especially after the COVID-19 pandemic. 
- However, mucormycosis in an immunocompetent patient is slowly gaining attention as few new cases have been reported throughout the world including the Indian subcontinent.
- Although, this disease is locally invasive, it may involve adjacent blood vessels and nerves. It may also exhibit a distant spread. 
- Radiographically, a variety of findings may be present, including lobar consolidation, isolated masses, nodular disease, and cavitation.
- The exact incidence of invasive Mucormycosis in India is unknown due to lack of population based studies.
- The ROCM type (45-74%) is the most common form followed by cutaneous (10-31%) disease in India. 
- Pulmonary Mucormycosis accounts for 3-22% of all cases. 

CASE REPORT
- 60 year-old male, smoker for 50 years.
- Presented with c/o: Right sided chest pain, streaky hemoptysis and change of voice for last 2 months. 
- Was taking symptomatic treatment along with anti-tuberculosis treatment (HRZE) for last 1 month.
- Patient was referred to us since there was no symptomatic relief.  
- Had a history of anti-tubercular treatment 20 years back. 
- Had no h/o diabetes mellitus, hypertension, known malignancy, COVID 19 infection, chronic steroid use or any other known immunocompromised condition in past. 
- O/E: Engorged neck veins and raised JVP along with anterior chest wall tender swelling on right side. 
- O/A: bilateral rhonchi were present.

On further work up 
- Initial hematological investigations: Unremarkable.
- Chest radiograph: Right upper zone heterogeneous opacity.
- Sputum cultures: sterile. 
- CECT (Thorax) : Ill-defined heterogeneous mass lesion in apical segment of right upper lobe with central necrosis. Anteriorly the lesion was causing erosion of manubrium sterni and first rib. Medially, it was encasing superior vena cava, bilateral brachiocephalic veins and azygous vein. 
- D/d: Lymphoproliferative disorders, primary lung mass, IFI, sclerosing mediastinitis due to tuberculosis, histoplasmosis or aspergillosis. 
- Bronchoscopy was performed: Showed no intraluminal growth.
- BAL fluid cytology: Aggregates of neutrophils and macrophages along with aseptate fungal hyphae raising a suspicion of fungal etiology. 
- For confirmation, USG guided Tru-cut biopsy was done. 
- HPE: broad, thin walled, aseptate fungal profiles with right angled branching consistent with Mucormycosis.
- To rule out other site of involvement, MRI head and PNS was done: no significant abnormity was seen. 
- Hence the diagnosis of Pulmonary Mucormycosis was established. 
- Patient was started on Liposomal Amphotericin-B and referred to CTVS department for surgical management.

DISCUSSION: 
- Mucormycosis is one of the most common IFIs after candidiasis and aspergillosis in immunocompromised patients.
- It’s rise in incidence parallels the rise in incidence of diabetes, cancer and need for organ transplantation. 
- However, occasionally it also occurs in the absence of risk factors.
- Diagnosis needs high index of suspicion, especially in patients without predisposition. 
- Diagnostic challenge of Pulmonary Mucormycosis: The diagnosis was difficult not only because the clinical presentation did not differ from primary lung mass, but also because the identification of the microbiologic agent is only possible after invasive lung biopsies and the use of non-widely available molecular biology methods.
- Current guidelines recommend a combined medical and surgical approach to management, as anti-fungal agents may have poor penetration at the site of the infection and the disease is rapidly progressive and associated with a bad prognosis. 
- This case describes the presentation, diagnosis, and timely treatment of a patient with pulmonary Mucormycosis. 

TAKE HOME MESSAGE: 
- Pulmonary Mucormycosis usually occurs as a disseminated form predominantly in individuals with predisposing factors. 
- However, rarely it can occur in individuals without risk factors and should be considered in the differential diagnosis of all individuals presenting with infiltrating lung and mediastinal masses.