CANDIDIASIS

 

• Candidiasis
• Candidiosis
• Candidosis
• Moniliasis

-          Infection of skin, mucosa and rarely of internal organs

-          Caused by a yeast like fungus, Candida albicans and occasionally by other Candida species

-          Candida albicans- Ovoid, spherical, budding yeast cell, which produces pseudomycelia both in culture and tissues

       Dimorphic fungi, existing in both mold and yeast forms.

 

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-          Candida species are normal inhabitants of the skin and mucosa - gastrointestinal tract, respiratory tract, vagina, and mouth.

-          Candidosis is an opportunistic endogenous infection

      -          A common predisposing factor is diabetes

-          Candida infections are rarely serious in  healthy people

-          Their growth is naturally suppressed by other normal microbiota but when these microbiotas are disrupted, Candida multiplies rapidly, producing candidiasis.

-          Also cause nosocomial blood infections in hospitalized patients.

-          In rare cases, it may spread through other parts of the body if the patient's immune system is not functioning properly-in severe cases it can affect the blood, the membrane lining the heart muscle (endocardium), or membranes around the brain (meninges).

Subdivisions of Candidiasis

• Candida Granuloma
• Candida Infection around the Nail-Paronichia
• Candidiasis of the Skin-Cutaneous Candidiasis
• Mucocutaneous Candidiasis, Chronic
• Oral Candidiasis
• Penis infections
• Systemic Candidiasis
• Thrush
• Vulvovaginitis, Caused by Candida

  

Signs & Symptoms

A very wide range of symptoms can be caused by the Candida infection, from the mildest and more common forms that usually affect the mouth and vagina, to the most rare and severe forms which may affect the heart or brain:

1) Candidiasis of the Skin (Cutaneous Candidiasis or Cutaneous Moniliasis)

-          Superficial skin infection is a common location for this fungal infection.

-          The lesions appear as red, sometimes itchy patches of varying sizes and shapes. The lesions are usually rimmed with small pustules and they commonly appear in folds of the skin; i.e., the underarms, under the breasts, the navel, groin or the folds of the buttocks (e.g. diaper rash)- Crusts may form on the scalp, possibly causing hair loss.

-          The infection may spread to the face, fingertips or the trunk. When the area around the anus is involved, the infection is called Perianal Candidiasis.

-           2) Vulvovaginitis or Vaginitis caused by Candida. Pregnant women or women with diabetes are more prone -usually first appears as a thick white or yellow acidic, vaginal discharge (leukorrhea) with itching and redness of the vagina and vulva.

3) Penis, infected by Candida. Infection of the tip of the penis (Glans Penis) with Candida -less common than Candidal Vaginitis. This infection may be seen in men whose sexual partners have Candidal vulvovaginitis and in men with Diabetes.

4) Oral Candidiasis (Thrush). Common in bottle fed infants and the aged and weak - affects the mouth. Creamy white patches or sores appear on the tongue or mucous membranes of the mouth. The corners of the mouth can become red (inflamed) and cracked.

5) Candida infection around the nails (Candidal Paronichia). Begin as a painful swelling that later develops pus. The infections may occur under the nails (subungual) possibly causing loss of fingernails or toenails. Common in occupations that require frequent immersion of hands in water (dishwasher, bartender etc)

6) Chronic Mucocutaneous Candidiasis (Candida Granuloma). This is a rare and severe form of Candidiasis, characterized by chronic infection of the skin, nails, scalp, and mucous membranes. This type of Candidiasis usually develops during infancy. It is characterized by red, pustular, crusted and thickened lesions, especially on the nose and forehead.

7) Systemic Candidiasis. Most serious Candida infection-affects many parts of the body and is usually caused by an immune deficiency. Inflammation of the membrane lining the heart (endocarditis), the membrane lining the skull (meningitis), or rarely inflammation of the bone (osteomyelitis) may also occur.

Bronchopulmonary candidosis is a rare complication of preexisting pulmonary or systemic disease

 8) Intestinal Candidiasis occurs commonly following an antibiotic treatment, as diarrhea not responding to treatment

Diagnosis

Microscopy and Culture

• Wet films or Gram stained smears from lesions/exudates show budding gram positive cells

-Candida is seen normally on skin/mucosa- its abundant presence is only of significance

-Demonstration of mycelial forms- indicate colonisation and tissue invasion –greater significance

• Cultures on SDA- creamy white colonies, smooth with a yeasty odour

-Candida albicans can be differentiated from other Candida species by growth characteristics, sugar assimilation and fermentation tests. 

-C. albicans alone forms chlamydospores on corn meal agar cultures at 20 degree Celsius

• Germ tube formation – ability to readily form germ tubes- within 2-3 hours, when incubated in human serum at 37 degree Celsius (Reynold’s Braude phenomenon)

• Serology- Antibodies/agglutinins appear in sera of patients but not helpful in diagnostic, since they occur in normal persons

Delayed hypersensitivity to Candida is universal- skin testing with Candida extracts indicates active functional cell mediated immunity-CMI

Treatment

• Management of Candidosis is by removal of predisposing causes.
• Amphotericin B, 5-fluorocytosine and clotrimazole used for disseminated candidosis
• Nystatin is effective, but poorly absorbed from gut- so not useful in systemic diseases