Rhinoscleroma

Background

Rhinoscleroma is an unusual chronic granulomatous disease of the upper airways. It commonly affects the nasal cavity (95% to 100%), but the nasopharynx (18% to 43%), larynx (15% to 40%), trachea (12%), and bronchi (2% to 7%). It is caused by Klebsiella rhinoscleromatis. It is not highly contagious.

Rhinoscleroma has been divided into 3 or 4 stages:

Catarrhal/atrophic
Granulomatous
Sclerotic stage

The catarrhal stage begins with a nonspecific rhinitis, which evolves into purulent, fetid rhinorrhea and crusting, lasting for weeks or months. The granulomatous stage leads to the nasal mucosa becoming bluish red and granular with intranasal rubbery nodules or polyps. Epistaxis (bloody nose) associated with nasal enlargement, deformity, and destruction of the nasal cartilage is noted (Hebra nose). This damage may progress to anosmia, anesthesia of the soft palate, enlargement of the uvula, dysphonia, and various degrees of airway obstruction. The fibrotic stage is characterized by sclerosis and fibrosis.

SYNONYMS Mikulicz disease

AGE RANGE-MEDIAN Second and third decades

SEX (M:F)
Slight female

GEOGRAPHY

Central and Eastern Europe
Low socioeconomic environments of Central and South America, Africa, the Middle East, Philippines, and India

Rare in the United States

EPIDEMIOLOGIC ASSOCIATIONS CHARACTERIZATION

Poor hygiene, crowded living conditions, and malnutrition Increase the risk for transmission

DISEASE ASSOCIATIONS CHARACTERIZATION

AIDS and other conditions with T-cell deficiency

PATHOGENESIS CHARACTERIZATION

Klebsiella rhinoscleromatis
Gram-negative, encapsulated, nonmotile, diplobacillus member of the family Enterobacteriaceae

Contracted directly by droplets or by contamination of material that is subsequently inhaled

Probably begins in areas of epithelial transition, as seen in the vestibule of the nose, subglottic area of the larynx, or between the nasopharynx and oropharynx

Cellular and humoral immunity
Cellular immunity is impaired in these patients however, the humoral immunity is preserved

CD4�CD8 ratio within the lesion is altered, showing decreased CD4 lymphocytes and increased CD8 lymphocytes, possibly inducing a diminished T-cell response

The macrophages are not fully activated

Mucopolysaccharides of the bacterial capsule probably contribute to inhibition of phagocytosis

LABORATORY/RADIOLOGIC/OTHER TESTS CHARACTERIZATION

Laboratory Markers

Cultures
A positive culture in MacConkey agar is diagnostic of rhinoscleroma, but cultures are positive in only 50% to 60% of cases

HISTOLOGICAL TYPES CHARACTERIZATION

General
Three stages, corresponding to the clinical stages

Only the granulomatous stage has diagnostic changes

Catarrhal/atrophic stage
Squamous metaplasia and a nonspecific subepithelial infiltrate of polymorphonuclear leukocytes with granulation tissue

Granulomatous stage

Diagnostic features are found in the granulomatous stage

Chronic inflammatory cells, Russell bodies, and pseudoepitheliomatous hyperplasia, groups of large vacuolated histiocytes containing the Klebsiella rhinoscleromatis (Mikulicz cells)

If numerous, they can be seen with hematoxylin-eosin stains, but may require periodic acid�Schiff, silver impregnation, or immunohistochemical stains for confirmation and identification

Sclerotic stage
Extensive fibrosis, which may lead to stenosis and disfiguration.

VARIANTS

SPECIAL STAINS/IMMUNOPEROXIDASE/OTHER CHARACTERIZATION

Special stains Bacteria seen by PAS,Giemsa, Gram, and silver stains

Electron microscopy (EM)
Large phagosomes filled with bacilli and surrounded by a finely granular or fibrillar material arranged radially

Represents accumulation of antibodies on the bacterial surface (type A granules), as well as aggregates of bacterial mucopolysaccharides surrounded by antibodies (type B granules)

DIFFERENTIAL DIAGNOSIS KEY DIFFERENTIATING FEATURES

Infectious granulomatous processes
Bacterial (tuberculosis, actinomycosis, syphilis, and leprosy)

Fungal (histoplasmosis, blastomycosis, paracoccidioidomycosis, and sporotrichosis)

Parasitic (mucocutaneous leishmaniasis)

Sarcoidosis

Vasculitis Wegener granulomatosis

Neoplastic diseases Lymphoma

Extranodal Rosai-Dorfman disease

PROGNOSIS AND TREATMENT CHARACTERIZATION

Prognostic Factors

Survival It is rarely lethal, unless it obstructs the airways

Recurrence Owing to a high incidence of recurrence, prolonged antibiotic therapy over months to years is necessary

Treatment
Tetracycline is the drug of choice

Other anbiotics inlude ciprofloxacin and rifampin

Steroids can improve the acute inflammatory symptoms

Surgery
Surgery and laser therapy are required to treat airway compromise and tissue deformity

Arch Pathol Lab Med 2001;125:157�158.
Arch Pathol Lab Med 2001;125:159-160.

Commonly Used Terms

Bacteria

Internet Links

Last Updated 11/8/2001

SYNONYMS	Mikulicz disease
AGE RANGE-MEDIAN	Second and third decades
SEX (M:F)	Slight female
GEOGRAPHY	Central and Eastern Europe Low socioeconomic environments of Central and South America, Africa, the Middle East, Philippines, and India Rare in the United States

EPIDEMIOLOGIC ASSOCIATIONS	CHARACTERIZATION
Poor hygiene, crowded living conditions, and malnutrition	Increase the risk for transmission

DISEASE ASSOCIATIONS	CHARACTERIZATION
AIDS and other conditions with T-cell deficiency

PATHOGENESIS	CHARACTERIZATION
Klebsiella rhinoscleromatis	Gram-negative, encapsulated, nonmotile, diplobacillus member of the family Enterobacteriaceae
	Contracted directly by droplets or by contamination of material that is subsequently inhaled
	Probably begins in areas of epithelial transition, as seen in the vestibule of the nose, subglottic area of the larynx, or between the nasopharynx and oropharynx
Cellular and humoral immunity	Cellular immunity is impaired in these patients however, the humoral immunity is preserved CD4�CD8 ratio within the lesion is altered, showing decreased CD4 lymphocytes and increased CD8 lymphocytes, possibly inducing a diminished T-cell response The macrophages are not fully activated Mucopolysaccharides of the bacterial capsule probably contribute to inhibition of phagocytosis

LABORATORY/RADIOLOGIC/OTHER TESTS	CHARACTERIZATION
Laboratory Markers
Cultures	A positive culture in MacConkey agar is diagnostic of rhinoscleroma, but cultures are positive in only 50% to 60% of cases

HISTOLOGICAL TYPES	CHARACTERIZATION
General	Three stages, corresponding to the clinical stages Only the granulomatous stage has diagnostic changes
Catarrhal/atrophic stage	Squamous metaplasia and a nonspecific subepithelial infiltrate of polymorphonuclear leukocytes with granulation tissue
Granulomatous stage	Diagnostic features are found in the granulomatous stage Chronic inflammatory cells, Russell bodies, and pseudoepitheliomatous hyperplasia, groups of large vacuolated histiocytes containing the Klebsiella rhinoscleromatis (Mikulicz cells) If numerous, they can be seen with hematoxylin-eosin stains, but may require periodic acid�Schiff, silver impregnation, or immunohistochemical stains for confirmation and identification
Sclerotic stage	Extensive fibrosis, which may lead to stenosis and disfiguration.
VARIANTS

DIFFERENTIAL DIAGNOSIS	KEY DIFFERENTIATING FEATURES
Infectious granulomatous processes	Bacterial (tuberculosis, actinomycosis, syphilis, and leprosy) Fungal (histoplasmosis, blastomycosis, paracoccidioidomycosis, and sporotrichosis) Parasitic (mucocutaneous leishmaniasis)
Sarcoidosis
Vasculitis	Wegener granulomatosis
Neoplastic diseases	Lymphoma
Extranodal Rosai-Dorfman disease

PROGNOSIS AND TREATMENT	CHARACTERIZATION
Prognostic Factors
Survival	It is rarely lethal, unless it obstructs the airways
Recurrence	Owing to a high incidence of recurrence, prolonged antibiotic therapy over months to years is necessary
Treatment	Tetracycline is the drug of choice Other anbiotics inlude ciprofloxacin and rifampin Steroids can improve the acute inflammatory symptoms
Surgery	Surgery and laser therapy are required to treat airway compromise and tissue deformity