Mucormycosis or Black Fungus Infection as it is being called is a Fungal infection affecting the Nasal, Oral regions more commonly. The other regions which it affects less commonly are Eyes, Cerebral, Lungs, etc. Mucormycosis is usually seen affecting people with reduced immunity – AIDS/HIV patients, patients on Corticosteroid medication – Organ transplant patients, auto immune disease patients, diabetic acidosis etc. /it is also seen to affect patients with predisposing factors such as Malignancy, burns, malnutrition, blood dyscrasias, renal failure as well. Mucormycosis or Black Fungus is quite commonly found in our everyday surroundings and we inhale or ingest the Spores regularly which are taken care of by our immunity.
Clinically Mucormycosis occurs in one of four forms – Rhinocerebral, Pulmonary, gastrointestinal and disseminated. The most common type is Rhinocerebral, as the fungal spores enter the body through the nose or mouth being inhaled through dirt particles and can occasionally spread to the Eye. It is also termed as Rhino-Maxillary type when the Maxilla and Nasal region are involved.
According to ijdr (Indian Journal of Dental Research):
“These fungi are ubiquitous, found in soil, bread molds, decaying fruits and vegetables. The most common form of mucormycosis is rhinocerebral and is usually seen in uncontrolled diabetes mellitus or in immunocompromised patients”
Symptoms of Oral Mucormycosis or Black Fungus:
With the Rhino-Maxillary Mucormycosis affecting multiple regions of the body, the most common being Oral, Nasal, Orbital and Cerebral. With the mode of entry into the body mostly being Nasal or Oral the first and initial symptoms are seen here –
- Bad Breath
- Redness and swelling of Gums
- Pus discharge from Gums
- Nasal Discharge
- Loosening of Teeth (Upper or Maxillary teeth in most cases)
- Ulceration with Ischemic Necrosis or Discoloration of the Palate (bony denudation in some cases)
- Pain in the Palate with soft tissue growth seen in some cases
- Headache and pain on one side of the face
- Extra-oral swelling on one side of Face – Middle third of face
Necrosis of the Palate – Is the most common symptom which is caused due to the involvement of the sphenopalatine and greater palatine arteries which result in thrombosis of the turbinate and then Necrosis of the palate.
In early stages of the disease, the patient has complained of Fever, headache, pain in the side of the face.
How does Mucormycosis Spread in the Body:
Fungal Spores of Mucormycosis enter the body through Nose or Mouth carried by dust etc. The infection starts in the palate or nasal mucosa and spreads into the paranasal sinuses, skin of the face cibriform plate and brain. The spread of the Fungal infection through this path is either by direct extension or through vascular channels.
If the Fungal spores enter the blood stream, it penetrates the arterial walls leading to endothelial damage which leads to intravascular thrombosis, infarction and necrosis of the tissue. Due to these factors Rhino-Cerebral form of Mucormycosis is the most common type – 1/3rd of all cases. It is further divided into two types based of the seriousness – Rhino-Maxillary is the less fatal form while the Rhine-Cerebral type is more invasive and life threatening.
Why is Mucormycosis aggressive and Life threatening in Diabetes patients?
It is due to the reduced defense response of the body and also the increase in micronutrients in the body such as Iron seen in Diabetic patients with high blood sugar levels.
Diagnosis of Rhino-maxillary Mucormycosis:
Early Diagnosis plays a major role in Prognosis of Mucormycosis due to rapid progression of the disease, early detection and Management of the Fungal infection can be life saving. Diagnosing the condition at an early stage can help in preventing irreversible Soft Tissue and Hard tissue damage. Let us look at the Differential Diagnosis of Mucormycosis of the Rhino-maxillary type.
Necrosis of the Hard Palate is also seen in Squamous Cell Carcinoma, Chronic Granulomatous infections like Tuberculosis, Wagners Granulomatosis, tertiary syphilis, midline lethal granuloma.
Mobility of Teeth or Pus discharge from Gums: This is also seen in conditions like Osteomyelitis, Chronic Suppurative Periodontitis, Syphilis, ANUG and patients on bisphosphonate therapy.
KOH (Potassium Hydroxide test):
A Specimen of the infected tissue is taken and placed in a Solution of 20% Potassium Hydroxide. This specimen is then viewed under a microscope to look for Fungal identifiers such as Hyphae etc.
This test helps in identifying whether it is a Fungal infection or not but does not identify the type of Fungal infection.
Radiographic Diagnosis of Rhino-Maxillary Mucormycosis:
The radiographic diagnostic aids used for diagnosis are PNS CBCT, CT and MRI.
CBCT findings for Mucormycosis:
- Opacification of Sinuses – Maxillary, Occipital, Sphenoid, Ethamoidal
- Mucosal thickening of Sinus walls with puss filled spaces.
- Bone loss around Maxillary teeth
MRI Findings of Mucormycosis: It is done to know the extent of the spread of the fungal infection to give a precise idea about the treatment plan and Management of the lesion.
Culture and Biopsy for Diagnosis:
Culture is done using “Sabourauds dextrose Agar” which helps in growing the Fungus
Biopsy is done by taking a specimen using H and E, PAS and later by using GMS Stain. In Biopsy the specimen shows long, broad, branching and Non-septate Hyphae of the Fungus.
Treatment of Rhino-Maxillary Oral Mucormycosis:
Rapid and Prompt treatment is required which can help in achieving good prognosis, due to the rapid progression of the disease.
- Systemic Antifungal Therapy: Amphotericin is used as Systemic or Topical Application form, in recent advancements the use of Posaconazole in addition to Amphotericin has shown excellent results.
- Surgical Debridement: Repeated surgical debridement is required to remove all necrotic tissue form Nasal region using – Nasal Endoscopic technique and Surgical debridement in the Palate or Maxillary region.
- Hyperbaric Oxygen therapy was found to be useful
- G-CSF – Granulocyte Colony Stimulating factor was found to be helpful
- Post OP closure of the Palatal Perforation using Free Flaps or Prosthesis is required post surgery and healing.
Note: Monitoring of Renal Complications is important during the use of Amphotericin-B as it is known to lead to Renal failures.