Centre For Training Research & Diagnosis Of Leishmaniasis – Diagnostic Services

Free diagnostic & support services

  • We offer a free weekly leishmaniasis patient care clinic to all state hospitals, all universities and all academic bodies.
  • This clinic is held on Tuesdays and Fridays at Department of Parasitology, Faculty of Medicine, University of Colombo.
  • Clinic is open from 8.00 a.m. to 12.00 noon except on public holidays. Alternative dates and time are available by appointment.

 

  • Sample collection for diagnosis of leishmaniasis ( see below for details), Laboratory investigations.
  • Technical advice on sample collection and transport.
  • Expert advice on case management and follow up.
  • Hospital visits on request for referrals.
  • Patient follow up service.
  • Diagnostic assistance to MLT/PHLTs (Technical officers) in health sector.
  • Cross examination support for patient samples reported elsewhere.

Samples, collection, transport and diagnosis

  • Light microscopy
  • In-vitro cultivation of parasites
  • PCR
  • rK39 serological assay

(Above investigations are carried out on skin lesion samples, bone marrow, blood and other organ tissues as appropriate).

Suspected cases of cutaneous/mucosal leishmaniasis:
for confirmation: aspirations, slit scrapings,  biopsies, touch smears.

 

Suspected cases of visceral leishmaniasis:
for screening: blood for rK39.
for confirmation: bone marrow, splenic/liver/lymph node aspirations.

Note: Instructions, collection tubes and requests forms are provided by the laboratory.

For microscopy:

  • We prefer to make smears by ourselves when samples are sent.
  • If necessary, draw a bedside smear, label, air dry, but do not stain, wrap individually and transport at room temperature.

 

For parasite cultures:

  • Add the sample to the tubes provided by us. You can use sterile plain bottles with 1-2 ml of normal saline if necessary.
  • Do not add formalin or any preservatives.
  • Prevent air drying and contamination.
  • Transport within 6 hours at room temperature.
  • If delayed, transport at +4 (in a flask with ice cubes) within 12 hours.

For PCR:

Note: Usually, same sample is used for both cultures and PCR examinations for clinician’s and patient’s convenience.

If separate samples sent,

  • Add the sample to the tubes provided by us or you can use sterile plain bottles
  • Do not add formalin or any preservatives
  • Prevent contamination.
  • Transport within at room temperature.

Parasitological confirmation (other than serological assays) are recommended.
Consult the laboratory clinicians before deciding on sample collection.

 

Screening assay: rk 39 dipstick test.
If negative: parasitological assays are required before exclusion.
Microscopy, culture or PCR of bone marrow, liver, spleen or lymph node aspirations are required.

  • Weekdays, until 1.00 pm in order to allow 3 hours for immediate processing required for parasite cultivation.
  • Other times, by prior appointment.
  • All state sector hospitals under health ministry.
  • Private sector hospitals in Colombo and other regions.
  • All hospitals under defense ministry.
  • All Universities (cross examination service).
  • All research and academic institutions.

Facts on diagnosis of leishmaniasis

  • Slit skin smear (SSS)
  • Lesion aspirate (LA)
  • Impression smears
  • Swabs from lesions
  • Punch biopsies

Sensitivity rate is around 60-70% at different endemic settings. Second line investigations are recommended in case LM is negative in a clinically suspected patient.

rK39 dipstick assay

Serological assays are performed mainly in VL. If positive, features of active VL should be there to confirm as VL.
If negative, parasitological methods are required before excluding.
Not useful in CL, since an increase of antibody level is not usually associated with CL.

Polymerase Chain Reaction (PCR) on lesion material/ Bone marrow