GEORGIA DEPARTMENT OF PUBLIC HEALTH

Case Studies Communication Works ?

11th National Conference on Laboratory Aspects of Tuberculosis/ Robin Connelly, MMSc, M (ASCP) CM, April 23, 2019

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Initial Communication

On a Thursday in the early eveningEmail sent from TB Program Physician regarding a positive GeneXpert sample that now had a positive culture at a local hospital. The physician stated the sample was Rifampin Resistant and he believed the isolate was at DPH and since the patient was already on a MDR regimen could it be sent to CDC for MDDR testing also.

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Investigation

On Friday Found that GPHL had received an isolate 3 days prior for susceptibility testing from a BAL collected 39 days previously and the susceptibility was ongoing

The isolate was forwarded to CDC on Friday for MDDR testing.

The physician was Emailed back that the specimen had been forwarded to CDC

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Additional Information

Probably due to low burden that did not meet the limit of detection.

Sputum collected at Health Department 11 days after BAL specimen at local hospital was tested with GeneXpert at GPHL and MTB was not detected. The sputum was culture positive for MTB

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Results from CDC received the next Wednesday

GEORGIA DEPARTMENT OF PUBLIC HEALTH

MGIT Susceptibility Results reported 7 days after initial communication

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Discordancy

Results from both MDDR and MGIT susceptibility were different than the GeneXpert

Because of the discordance CDC asked for our hospital partner to review that the correct specimen was forwarded and to send the graph for review.

GEORGIA DEPARTMENT OF PUBLIC HEALTH

GeneXpert Result Review

• Max threshold

Probe A Ct value 31.7 39.0Probe B Ct value 0.0 39.0Probe C Ct value 0.0 39.0Probe D Ct value 32.0 36.0Probe E Ct value 33.3 36.0

GEORGIA DEPARTMENT OF PUBLIC HEALTH

GeneXpert Package Insert

Specimens that have both MTB-complex DNA and rifampin-resistance associated mutations of the rpoB gene detected by the Xpert MTB/RIF Assay must have results confirmed by a reference laboratory.

The Xpert is intended for use for raw sputum samples and for concentrated sputum sediments.

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Questions

The GeneXpert was performed on a BAL specimen. How many of us have validated the GeneXpert for specimens other than sputum?

How did you validate?

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Questions

Was the GeneXpert actually performed on the BAL specimen from August or a new BAL specimen collected in October? If it was October was the patient already on TB meds?

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Conclusions

Based on the MDDR the TB program physicians recommended the patient be switched to “standard” therapy without waiting for conventional DST

Patient started on RIPE 19 days following initial communication

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Acknowledgements

Dr. Beverly Metchock CDC

Dr. Marcos Coutinho-Schechter GA TB Program

Dr. Alawode Oladele DeKalb County

Dr. Tonia Parrott GPHL

GEORGIA DEPARTMENT OF PUBLIC HEALTH

Happy Medical Laboratory Professionals Week