Black fungus/Mucormycosis -A post covid oral complication

• Mucormycosis, also known as Black Fungus, is a serious but rare fungal infection caused by a group of invasive infections caused by filamentous fungi of the Mucoraceae family, which is live throughout the environment. 

• The fungi responsible for these infections are found in different environmental niches like soil, decaying vegetables, bread, and even dust.

•  Mucormycosis fungus is not a new disease, but the severity of it is more dangerous when Covid patients develop this disease.

• Black fungus is a misnomer... the colour of fungus is not black but because of decreased blood supply in the affected area causing necrosis.., it may give a feeling that the area has become black, that is why the name has come.
• Mortality rate is 50%.

Causes

It is caused by filamentous fungi.

Kingdom	Fungi
Subphylum	Mucoromycotina
Order	Mucorales
Family	Mucoraceae
Genera (Frequency of infection)	Rhizopus	47%
	Mucor	18%
	Cunningghamella	7%
	Apophysomyces	5%
	Lictheimia	5%
	Saksenaea	5%
	Rhizomucor	4%

MAJOR ROUTE OF INFECTION

 Inhalation
 Ingestion
 Traumatic inoculation

Risk factor

Mucormycosis is a rare infection. The infection is more common among people with

weakened immune system.

• Uncontrolled Diabetes/Ketoacidosis
• Neutropenia Patients(low white blood cells)
• Immunocompromised:-Hiv/AIDS/Cancer or on chemotherapy, Chronic kidney disease, Organ transplant.
• Increased serum Iron
• Chronic Corticosteroid treatment
• Skin trauma
• Post covid-19(patients on steroids, ventilators, misuse of steroids)

Types 

1. Rhino-cerebral
2. Pulmonary
3. Disseminated
4. Cutaneous/Soft tissue
5. Gastro-Intestinal 

 symptoms

Common symptoms:

• Unilateral Headache
  
• Unilateral Facial pain
• Pain in region of sinusis
• Unilateral Numbness in face
• Nasal congestion
• one side nose obstructions (difficulty in breathing)
• Unilateral swelling of eyes or check
• Black dry crusts in the nose or cheek
• Foul-smelling blood-tinged  Nasal discharge
• Double vision(diplopia), Blurred vision,loss of vision,Ptosis
• Restriction or loss of eye moment
• Neurological symptoms
• Fever, cough, chest pain
• Abdominal pain, Vomiting

Dental findings:

1. 

   Necrosis of hard palate 

   Loosening of the tooth
2. Dental pain
3. Halitosis
4. Pus discharge from the mouth(intraoral draining sinuses)
5. Exposed palatal bone
6. Ulceration and blackening of the mucosa
7. Mobility of maxilla
   

Pathophysiology

 Angioinvasion
 Vessel thrombosis

 Ischemia
 Tissue necrosis

Pathogenesis of mucormycosis

Is mucormycosis contagious?

No. Mucormycosis can’t spread between people or between people and animals.

Mucormycosis /Black fungus and covid 19

• Mucormycosis has been reported in many states in India in recovered patients with covid 19.

• The infection may occur during covid 19 infection or a few weeks after recovery from covid 19.

• Many states in India have declared mucormycosis an epidemic.

• Covid 19 disease itself is associated with leucopenia and may lead to immune compromise caused by an impaired immune response

• Steroids are being used in covid 19 patients to reduce inflammation in the lungs. This may lead to an increase in blood sugar levels in diabetics as well as non-diabetics.

• Misuse of steroids during this second wave of covid 19 can also be contributing factor for mucormycosis.

• The coexistence of covid 19 infections with high blood sugar levels and immunosuppressive treatments would expectedly increase the incidence and severity of mucormycosis.

• Rhino Orbital cerebral mucormycosis(ROCM) is being reported in covid 19 patients.

• It starts with Paranasal inhalation f spores and the formation of coenocytic hyphae, Then proliferate in the sinuses and can find their way t the orbit either through direct invasin r via nasolacrimal duct. It can gain access to the brain either via spread from the orbital apex, cavernous sinus, through cribriform plate r through blood vessels.

Pathogenesis of Mucermycosis in covid19 patients

Diagnosis

• Medical history, symptoms, physical examinations
• Nose endoscopy
• Tissue biopsy
• Laboratory test(culture sampling, histopathological): Characteristic feature being an aseptate hyphal element that branch at right angles)
• CT scan  with contrast/ MRI of your lungs, sinuses, or other parts of your body, depending on the location of the suspected infection

Treatment

The key to a predictable treatment outcome is early detection and early treatment.

Multidisciplinary approach: ENT surgeon, oral and maxillofacial surgeon, Ophthalmologist, Neurologist, Microbiologist, Internal medicine specialist.

1. The mild form can be corrected merely by antifungal medicine called Amphotericin B.
2. The moderate form could involve some areas of the sinus, nose, throat, and upper jaw which would require surgical intervention.
3. The severe form of the disease could involve the eyeball leading to blindness, or encroach the cavernous sinus leading to death.

Treatment of Mucormycosis/black fungus

Role of Dentist

• Early detection
• Dual role in clearance surgery as well as post mucormycosis reconstruction.
• Dental rehabilitation
• Resection of involved jawbones.
• Reconstruction

Oral Manifestations of COVID 19

 INTRODUCTION

•  The Coronavirus disease 2019(COVID-19) caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).
• The Virus was first identified in December 2019 in Wuhan, China.
• Pandemic:11th March 2020
• India's first case:30th January 2020

Modes of Spread

Respiratory droplets while sneezing, coughing, speaking.

Morphology

Structure of Coronavirus

Family: Coronaviridae
Genome:ssRNA
Size:120nm
Shape: Crown like or Coronal

General pathogenesis

Oral Pathogenesis

Symptoms

Most common symptoms:

• fever
• dry cough
• tiredness

Less common symptoms:

• aches and pains
• sore throat
• diarrhea
• conjunctivitis
• headache
• loss of taste or smell
• a rash on the skin, or discolouration of fingers or toes

Serious symptoms:

• difficulty breathing or shortness of breath
• chest pain or pressure
• loss of speech or movement

Oral Manifestations of COVID 19

Dysgeusia(loss of taste) is the first recognized oral symptom of novel coronavirus disease (COVID-19).

• Virus distrust cranial nerve 1,7,9,10

1. Dry mouth/Xerostromia: The most common reason for mouth breathing by an individual is due to mask use. Mouth breathing can desiccate oral tissue, especially without frequent hydration. Studies suggest that another biological mechanism involves viral entry into the salivary glands, which are known to be abundant in the ACE2 receptor.
2. Mouth Ulcers: Painful mouth ulcers can be in the tongue, lips,

   

   Mouth ulcers in covid19

    and palate. Coronavirus is known to cause vascularity anomalies due to viral damage of blood vessels. The virus gains entry into the endothelial cells that line blood vessels via the ACE2 receptor and damages them, leading to tissue necrosis, including oral ulcerations. The tissue damage can be further exacerbated by increased inflammation.
   
3. Covid tongue: COVID Tongue, is a symptom that is not very common but is being reported by COVID positive patient. Doctors are trying to identify the reason behind the new symptoms, it can be due to a newer version of mutated covid19virus. Covid tongue mainly starts with irritation, itching, a vague sensation of pain, and extreme dryness of the mouth with the rare occurrence of mouth ulcers. According to the American Academy of Oral Medicine (AAOM), the COVID tongue is an inflammatory disorder that usually appears on the top and sides of the tongue. In the Covid tongue, your mouth fails to produce saliva and you experience dryness, white patches, and bumps on your tongue. Saliva functions as a protection against bad bacteria and in its absence your body will be exposed to them.

   

   Covid Tongue

   • Atrophy of tongue

   • Ulcers on tongue
   • Fissures on tongue
   • Bumps on tongue

4. Gingival inflammation: It can be Due to generalised increase in cytokines and interleukins due to coronavirus19.The inflammatory products can enter the bloodstream through infected gum pockets around the teeth, When inflammatory products from gum disease enter the bloodstream, those products can go to other body organs and potentially cause tissue damage.
5. Herpatiform/zosteriform lesions: Multiple painful, round yellowish-Grey ulcers with an erythematous rim on both keratinised and non keratinised mucosa. Stress and immunosuppression associated with covid 19 is a suggestive cause of the appearance of secondary hepatic gingivostomatitis.
6. Ulcers and erosion: Painful lesions with irregular borders on the tongue, hard palate, and labial mucosa. Different factors such as drug eruption, vasculitis, or thrombotic vasculopathy secondary to covid19 were suggestive as the cause of the development of ulcerative and erosive lesions.
7. White/Red plaques: Reported on the dorsum of the tongue. gingiva and palate of conformed and suspected covid 19 patients. Candidiasis due to long-term antibiotic therapy, poor oral hygiene can be the reason for white and red patches.

8. 

   Petechiae

   Kawasaki-like disease:  Oral lesions including cheilitis, glossitis, Erythematous and swollen tongue(red strawberry tongue)
9. Petechiae: In few cases, petechiae was reported on the lower lip, palate, and oropharynx mucosa. Thrombocytopenia from covid19 infection and prescribed drugs were the suggestive causes of the lesions.
   
10. Erythemamultiforme like lesions: Lesions appears like blisters, desquamative gingivitis, erythematous macules, erosions, painful cheilitis with hemorrhagic crust on the lips.

Management of oral lesions

Conclusion

• Oral Symptoms can also be considered initial symptoms of covid-19.
• Oral manifestation of covid 19 has been widely recognised, however, the pathognomic lesions of covid 19 are still uncertain
• Oral manifestations that may appear in covid19 patients can be important for early detection and prevention of transmission, because oral manifestations in covid 19 could mimic other viral manifestations, including herpes zoster.
• studies are recommended to determine the relationship between covid 19 and manifestations in the oral mucosa.