Case 3: what grew? BA Gram stain morphology Mucoid colonies on BA

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1 Case 3: what grew? BA Gram stain morphology Mucoid colonies on BA 43

2 Case 3: probability split! Gram variable, grows on BA, MAC, barely on CHOC Oxidase positive Vitek: probability split, Acinetobacter versus Moraxella API 20NE: Choose from one of 5 Moraxella species Positive oxidase rules out Acinetobacter Can Moraxella grow on MAC? Yes, atlantae, canis, osloensis Call it Moraxella species, get it out the door! 44

3 Organism identification policy Specify primary method, secondary method, additional tests, establish acceptable probability such as >=90% MIC without interpretation if needed Contact microbiology if definitive ID needed 45

4 Case 3: summary Develop policies to handle problem bugs to minimize waste of time and supplies Quote from Organism Identification Policy: Repeated, drawn out, and heroic attempts to speciate organisms do not in most instances contribute to patient outcome. In most cases, they simply waste time and money. How many ID attempts using proper CPT code can you bill? 46

5 Case 4: it must grow! 35 year old female Cystic fibrosis Bilateral lung transplant SCC of the head and neck Radiation injuries from treatments Stage 3 chronic kidney disease Hypertension Mastoidectomy Sepsis? 47

6 Admitted for neutropenic fever, anemia, volume depletion Case 4 Let s do vancomycin, flagyl, and cefepime first and then let s do a spinal tap and order everything! Let s call the lab every 8 hours until something grows! Routine, AFB, fungus, HSV, CMV and Toxo PCR Cell count, India ink, Cryptococcal antigen, protein, glucose 48

7 Case 4: CSF results Cryptococcal antigen and India ink negative Glucose 41 Total protein 143 Cell count: colorless, cloudy RBCs 13/ml WBCS 2176/ml with 93% neutrophils CBC WBC was 15.2 with 84% neutrophils 49

8 Case 4 Gram stain on cytocentrifuged smear: Many leukocytes seen Few erythrocytes seen No bacteria seen 50

9 Case 4: your diagnosis? a) Viral meningitis b) TB meningitis c) Naegleria encephalitis d) Aseptic meningitis 51

10 Case 4: the rest of the story Patient had been given cetuximab! This is a case of drug-induced aseptic meningitis! 52

11 Case 4: the rest of the story 53

12 Case 4: summary It is very 3 tempting to see bugs (ones not really there) in a CSF with all those PMNS. The doctors don t always talk to each other The doctors don t always talk to the lab The ID pharmacist told us the rest of the story regarding cetuximab. 54

13 Case 5: unknown yeast? 76 yr old male with dysphagia, pain swallowing Base of skull osteomyelitis, sphenoid, mastoid involvement, opacification of bilateral mastoid air cells and right middle ear cavity After six weeks of cefepime, things get worse Multiple surgical specimens submitted: mastoid, sphenoid, middle ear fluid, rt sinus contents. 55

14 Mastoid Gram stain 56

15 Mastoid Gram stain Also seen with calcofluor white stain 57

16 Mastoid Gram stain 58

17 Case 5: what do you think it is? a) Candida b) Malassezia c) Microsporidia d) Sporothrix 59

18 Case 5: no growth to date Supplemented media with olive oil Voriconazole added to Vanc, Cipro, Flagyl Confounding noise: Sphenoid contents grew Aspergillus fumigatus, Enterococcus and Corynebacterium species 60

19 Case 5: pathology report Right mastoid mucosa Simple cuboidal epithelium with hemosiderin and chronic inflammation Abundant calcification present No evidence of malignancy or dysplasia GMS stain negative for fungal organisms 61

20 Case 5 mastoid tissue Let s order $$ molecular from UWMC No bacterial DNA detected with 16S rdna primer set No fungal DNA detected with 28S rdna and ITS primer sets No M. tuberculosis detected with hsp65 amplified probe No nontuberculous Mycobacteria detected with 16s rdna, hsp65 and rpob primer sets 62

21 Case 5: Let it go, let it go The weird bug has not grown. The patient is doing better. Sometimes we see things that don t grow. 63

22 Gram stain improvements? Flocked swabs: do they improve Gram stains by elution or reduce sensitivity by dilution? TLA? Are the Gram stains better? Automated gram stainers? Do you have one? Do you want one? 64