Actinomycosis

• A. Israelii – the commonest• A .Meyeri• A.Naeslundii• A.Odontolyticus• A. Viscosus

Actinomycosis

ACTINOMYCOSISNot highly virulent (Opportunist)– Component of Oral Flora• Periodontal pockets• Dental plaque• Tonsilar crypts

– Take advantage of injury to penetrate mucosal barriers• Coincident infection• Trauma• Surgery

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PEOPLE AT RISK WITH ACTINOMYCOSIS • Having a dental disease or recent dental surgery (for

jaw abscess)• Aspiration (liquids or solids are sucked into lungs)

(for lung abscess)• Having bowel surgery (for abdominal abscess)• For women: having an intrauterine contraceptive

device (IUD) in place for many years (for abscess affecting the reproductive organs)

Cervicofacial Actinomycosis • This is the most common and recognized

presentation of the disease.• Actinomyces species are commonly present in

high concentrations in tonsillar crypts and gingivodental crevices.

• Many patients have a history of poor dentition, oral surgery or dental procedures, or trauma to the oral cavity.

• Chronic tonsillitis, mastoiditis, and otitis are also important risk factors for actinomycosis.

Infection Cervicofacial region

• Periostitis or osteomyelitis can develop if the infection extends to facial and maxillary bones. The mandible appears to be one of the most common osteomyelitis sites.

Abdominal Actinomycosis

Examination of discharges will help in diagnosis

• Examination of drained fluid under a microscope shows "sulphur granules" in the fluid. They are yellowish granules made of clumped organisms

Dr.T.V.Rao MD 12

Typical appearance of histopathological examination with special stains

• The smears revealed radiating filamentous colonies of Actinomyces in a background of neutrophilic exudates; PAS stain also showed Actinomyces colonies.

Dr.T.V.Rao MD 16

Mycetoma • Mycetoma is a chronic subcutaneous

infection caused by actinomycetes or fungi. • This infection results in a

granulomatous inflammatory response in the deep dermis and subcutaneous tissue, which can extend to the underlying bone.

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Mycetoma • Mycetoma is characterized by the

formation of grains containing aggregates of the causative organisms that may be discharged onto the skin surface through multiple sinuses.

• Mycetoma was first described in the mid 1800s and initially named Madura foot, after the region of Madura in India where the disease was first identified.

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• Slow spreading skin infection • Local swelling • Small hard painless nodules • Ulceration • Pus discharge • Sinuses • Scarred skin & discolouration • Itching • Pain & Burning sensation if superinfected

Clinical features

• Direct microscopy: • Blood- Leukocytosis & neutrophilia• Culture of exudates • Skin biopsy• Serology.

Lab studies

Excised mycetoma showing a draining sinus(cut open in this preparation) containing black grains.

H&E stainskin biopsy

H&E stained tissue section showing blacked grained eumycotic mycetoma caused by Madurella mycetomatis.

• Granulomatous Inflammation With Abscess Formation.

• A Central Zone Exists Where Polymorphonuclear Cells Are Abundant And Granules Or Grains Are Found.

• This Central Zone Is Surrounded By Lymphocytes, Plasma Cells, Histiocytes, And Fibroblasts.

Histopathological Findings