Mycobacteraemia - Hospital Blood Culture Guidelines

Indication

Strong clinical indicators HIV seropositivity Immunosuppression e.g. chemotherapy, organ transplant recipient or low CD4 count (<100 cells / ml) Neonate from untreated maternal mycobacteraemia

+

Associated with a history of Tuberculosis AIDS Anaemia Chronic pyrexia Chronic cough Intravenous Drug Use

>

? Mycobacteraemia

Method

If tuberculous or atypical mycobacterial bacteraemia is suspected, advice regarding diagnosis and treatment can be sought from Dr William Hope, UHSM TB Lead or Dr M. Cullen, Consultant Microbiologist.

Samples should be collected before antibiotic therapy is commenced to allow growth and identification of any mycobacteria present. Standard blood culture bottles will not grow mycobacteria. Delivery of mycobacterial blood culture bottles can be arranged by contacting the Microbiology Laboratory on extension 4819. One mycobacterial blood culture bottle (Biomeriéux BacT/Alert MB) should be used per patient, inoculating with 5 ml of the patient's blood.

Culture of blood for mycobacteria requires the addition of a supplement to the culture bottle within 12-24 hours of collection. Prior arrangement with the microbiology laboratory at Wythenshawe Hospital is essential to allow correct timing of this procedure. The samples are processed at University Hospital Aintree, Liverpool and the laboratory at Wythenshawe will arrange transportation there. Whenever possible, arrange for blood collection in the morning so that samples are in the Wythenshawe laboratory by 10:30 am. Out of hours, please discuss arrangements with the Microbiologist on-call (it may be appropriate to place the bottle in an incubator until next morning).

Phlebotomy

• Telephone the microbiology laboratory in advance to inform them of the imminent arrival of the specimen.

• Pre-label the BacT/Alert MB culture bottle with the patient's name, date of birth and hospital number. Complete a microbiology specimen request form giving the working diagnosis and any clinically appropriate information.

• Use personal protective equipment as appropriate.

• Perform venepuncture and inoculate the blood culture bottle using aseptic technique.

• The bottle must be replaced in the small cardboard transport box provided before inserting in the sealable plastic specimen bag together with the request form.

• Transport samples to Wythenshawe Microbiology Laboratory as soon as possible. The pneumatic tube may be used with appropriate packaging.

Bone marrow aspirates may also be inoculated directly into BacT/Alert MB culture bottles when appropriate.

Useful contacts

Wythenshawe Hospital

Microbiology Laboratory Enquiries 4819/ 4772

Dr William Hope, Clinical Lead for TB via switchboard

Clinical Microbiologists 2885

Guideline Details

Produced by Drs. F. Awan (F2 Microbiology) and M. Cullen (Consultant Microbiologist)

Last reviewed January 2010