Types of Fungal Sinusitis

Dr. K. R. Meghanadh

Fungal sinusitis is a condition caused by fungus. Fungi are present everywhere in the environment and enter our bodies daily. They are simply incapable of attacking an average human. But whenever a person has compromised immunity or fluid stagnates for a prolonged time in the sinuses, the fungi will thrive in it and cause fungal sinusitis. Unlike bacterial and allergic sinusitis, fungal sinusitis is on the rarer end. In this article, we will delve into three distinct types of fungal sinusitis. Each has its own set of characteristics, symptoms, and treatment approaches.

It's crucial to understand that individuals can experience various types of sinus infections simultaneously, with bacterial and fungal infections coexisting in different sinuses. Furthermore, both invasive and non-invasive forms of fungal infections may occur concurrently. The multitude of potential combinations complicates the diagnosis significantly, making it a challenging step in the process. However, once an accurate diagnosis is achieved, the chances of successfully addressing the issue are considerably higher.

Fungal Sinusitis Types

Fungal sinusitis can be classified into three types based on the behavior of the disease, and this classification is irrespective of the specific type of fungi causing the infection.

1. Non-Invasive Fungal Sinusitis

2. Invasive fungal sinusitis

3. Fulminant fungal sinusitis

Non-Invasive Fungal Sinusitis

Non-invasive fungal sinusitis occurs when the fungus resides within the sinus cavity without penetrating the sinus wall or surrounding tissue. In this form, our body's immune response establishes a protective barrier within the sinuses to prevent the fungus from spreading. However, when immunity is compromised, as in the case of viral infections, uncontrolled diabetes, etc., there is a risk of the fungus invading tissues, leading to the development of invasive fungal sinusitis. Non-invasive fungal sinusitis is the most common among the three types and is generally considered the least dangerous, often persisting for an extended period.

Cause

There are many theories on how fungal sinusitis starts, but the most convincing one is that initially, the sinusitis starts off as bacterial. Our immunity tries fighting the disease by sending WBCs into the sinuses. Once the fight with the bacteria is over, WBCs and dead bacteria simply cannot go back into the bloodstream, so the only way is to escape through the sinus drainage pathway, which will be blocked due to the existing infection. The dead WBCs and bacteria will turn into food for the fungus providing an ideal environment for it to grow.

Fungal sinusitis could occur only in a few sinuses, and the rest can have bacterial infection or no infection.

Sub-Types

There are two types of non-invasive fungal sinusitis:

1.      Allergic fungal rhinosinusitis

2.      Fungal ball

Allergic fungal rhinosinusitis

In allergic fungal rhinosinusitis, most problems are due to allergies. The fungus is very limited in number, but the body overreacts to the fungus. Usually, in allergic fungal rhinosinusitis, there will be a strong allergic reaction from the body to minimal fungus. If there is no reaction, then the fungus will increase.

Fungal ball in sinuses

In a fungal ball, there will be a massive amount of fungal material, and the body will not respond. The body responds to an outside organism in two ways: one is an allergic type, and the other is a killing one. If the allergic type is more, they will develop allergic fungal rhinosinusitis. If the response for the body is very negligible, then it grows into a fungal ball.

Symptoms

As mentioned earlier, the fungal symptoms will depend on the type of non-invasive fungal infection.

Fungal balls will have no or very mild symptoms, and any symptoms are mostly due to bacterial sinusitis.

Allergic fungal rhinosinusitis, on the other hand, can have symptoms on the extreme side, although the disease internally need not be as severe as a fungal ball.

Here is the list of symptoms shown for non-invasive fungal sinusitis.

• Runny nose

• Nose block

• Headache

• Facial pain

• Phlegm oozes from the nose to the back of the throat, thus a need to clear the throat.

• Sore throat

• Frequent attacks of cough

Diagnosis

Diagnosing non-invasive fungal sinusitis based on symptoms can be challenging, particularly when dealing with fungal ball cases, as the symptoms often overlap with those of allergies or bacterial sinusitis. Physicians typically rely on endoscopy and CT scans for diagnosis. If fungal material is discovered during endoscopy, confirmation of the fungal infection is achieved through a culture and microscopic examination. Additionally, a fungal smear, such as a potassium hydroxide smear, will identify fungus broadly, but it will give a good idea about the fungus that can be used in devising the plan to treat non-invasive fungal sinusitis.

It is noteworthy that many instances of fungal ball sinusitis have been incidentally detected during CT scans conducted for unrelated issues. In such cases, patients may be unaware of the presence of a sinus infection. In contrast, the severity of symptoms in allergic fungal rhinosinusitis serves as a key indicator for Ear, Nose, and Throat (ENT) specialists.

Treatment

Non-invasive fungal sinusitis, which is found within the sinuses, requires sinus surgery since antifungals can't reach the affected area.

Fungal Ball Sinusitis

Doctors will do sinus surgery to remove the fungus and other fluids. They make corrections in the sinus drainage to prevent further fluid stagnation.

Allergic fungal rhinosinusitis

A combination of antiallergic medication and sinus surgery is advised for treating this. Although symptoms often improve with antiallergics. If significant fungal presence persists, antifungals may be prescribed.

Invasive Fungal Sinusitis

Invasive fungal sinusitis occurs when the fungal infection extends beyond the sinus cavity and invades the tissues, potentially leading to serious complications. This type of infection is considered more dangerous than non-invasive because it can cause tissue damage.

Cause

Non-invasive fungal sinusitis can turn into invasive when fungus in the sinuses breaks the protective barrier that is created by our body’s immune system. This can happen mostly when our immunity is down.

Types

They are two distinct forms of invasive fungal sinusitis

1. Granulomatous invasive fungal sinusitis

2. Non-granulomatous invasive fungal sinusitis

Granulomas, immune system cells, develop around a fungal infection, defining it as granulomatous fungal sinusitis. Without granulomas, it is non-granulomatous fungal sinusitis. Recovery is quicker with the right medications for granulomatous cases than non-granulomatous fungal sinus infections.

Symptoms

• Pain and/or swelling in the eye, nose, teeth, or cheek

• Vision disturbances – double vision or diminishing vision

• Loosening of the teeth when the infection spreads to the jaw bone

• Loss of sensation in the cheek

• Swelling of the face if it spreads to the skin – a rare condition

• When it spreads to the brain, the body part controlled by that part of a particular brain area will be affected.

Diagnosis

Diagnosing invasive fungal sinusitis is very tricky for an ENT doctor. It needs a biopsy, where a small piece of infected tissue is removed and sent to the lab for testing. Picking out the tissue representing the disease and giving proper instructions to the pathologist is the trickiest part.

Treatment

The treatment for granulomatous or non-granulomatous invasive fungal sinusitis revolves around antifungal medication. Doctors will prescribe antifungal drugs to target and eliminate the fungal infection. Doctors should not opt for surgical procedures like debridement in invasive.

Fulminant Fungal Sinusitis

Although fulminant fungal infection can fall under the category of invasive sinusitis as the infection is into the tissues, the term "invasive fungal sinusitis" typically denotes the non-fulminant variant. This is a fatal disease.

Fulminant infections exhibit an exceptionally rapid fungal spread, not only within the tissues but also through the bloodstream. Fulminant fungal sinusitis is even more rare than invasive fungal sinusitis and far more dangerous when compared to invasive fungal sinusitis. Invasive can take years to reach the brain and kill a person, whereas fulminant will need just a few weeks. In fact, depending on the immunity, the fungus can double within a few hours if powerful IV antifungals are not administered.

Types

We can divide fulminants based on the types of fungus that have attacked. It can be caused by

1. Mucor–mucormycosis

2. Candida – Candidiasis

3. Aspergillosis

While fulminant infection caused by mucor is commonly called black fungus, the

Cause

Fulminant fungal infection, irrespective of the type of fungus, this type of fungal sinusitis occurs only when the immune system is at an extreme low. The above-mentioned fungi are commonly found in the environment, and we are always exposed to them. Only when immunity takes a huge blow can these fungi attack us.

The main causes that give such a blow and cause fulminant infection are

• Organ transplant patients on immune suppressants

• Cancer patients on anti-cancer drugs

• Immune deficiency syndromes Eg: AIDS

• Patients who are on steroids for months

• Uncontrolled diabetic patients

• COVID-19

Symptoms

Although there is a list of symptoms for fulminant invasive fungal sinusitis, it is easy for us or the doctor to identify based on the first symptom itself. The first symptom is severe facial pain that cannot be subsided with painkillers. So, we can experience severe pain in

• Cheeks

• Teeth

• Eye

The other list of symptoms follow later.

• Nose block

• Nasal discharge

• Double vision

• Deterioration of eyesight

• Swelling of the eye, nose, or cheek

• Watering of the eye

• Redness of the eye

Diagnosis

Fulminant fungal infection is diagnosed using nasal endoscopy followed by culture and biopsy of the substance found in the nose.

As mentioned earlier, the severe facial pain symptom usually triggers doubt in an ENT.

Treatment

The treatment of fulminant fungal sinusitis requires a comprehensive approach, incorporating multiple surgical debridement procedures and the administration of powerful antifungal medications. The treatment approach will be both vigorous and customized based on the specific condition of the patient.

It is very important to start the fulminant fungal sinusitis treatment with strong antifungals through IV on suspicion before the lab results arrive, as a delay in the confirmation can alter the fate of a person.

Dr. K. R. Meghanadh