title: A rare actinomycosis of humerus: an unusual location and a diagnostic dilemma. A case report.
abstract: BACKGROUND
  Isolated actinomycosis of the humerus is a very rare entity.
  
  
  METHODS
  A 30-year-old male had an erythematous plaque with a pus-(minimal) discharging sinus over left lower arm. The patient had no discharge of sulphur granules from the sinus. The patient had raised ESR with a single lytic lesion with minimal sclerosis and inconspicuous periosteal reaction on radiographs. Such atypical clinical and radiological features lead to initial wrong diagnosis of tuberculosis. A diagnosis of Actinomycosis of humerus became possible after demonstration of filamentous bacilli in culture and on histopathology from the sulphur grains obtained by open biopsy.
  
  
  RESULTS
  The patient recovered completely after administering PenicillinG 24 million units intravenous for 7 days followed by 1.2 g of oral amoxicillin in three divided doses for 3 months and did not show any recurrence during last 2 years of follow up.
  
  
  CONCLUSIONS
  Surgeons should be aware of this rare entity and difficulty in its diagnosis due to its variable manifestations, including confusion with highly endemic tuberculous infection. Awareness of full spectrum of the diseases and careful evaluation in individual cases will expedite diagnosis and avoid unnecessary surgical interventions.
authors.affiliation: Department of Orthopaedics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110 029, India. ashok@k73rediffmail.com
authors.forename: Ashok
authors.initials: A
authors.lastname: Kumar
authors.forename: Manish Kumar
authors.initials: MK
authors.lastname: Varshney
authors.forename: Vivek
authors.initials: V
authors.lastname: Trikha
authors.forename: Shah Alam
authors.initials: SA
authors.lastname: Khan
authors.forename: C S
authors.initials: CS
authors.lastname: Yadav
authors.forename: Azra S
authors.initials: AS
authors.lastname: Hasan
mesh_terms: D000196:Actinomycosis / Q000175:diagnosis* / Q000188:drug therapy; D000328:Adult; D000658:Amoxicillin / Q000008:administration & dosage; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D001850:Bone Diseases, Infectious / Q000175:diagnosis* / Q000188:drug therapy; D006801:Humans; D006811:Humerus / Q000000981:diagnostic imaging / Q000382:microbiology*; D008297:Male; D010400:Penicillin G / Q000008:administration & dosage; D011859:Radiography
chemical_list: D000900:Anti-Bacterial Agents; D000658:Amoxicillin; D010400:Penicillin G