18 April 2026
: Case report 
Cefiderocol Heteroresistance in NDM-Producing Enterobacterales: A Complex Polymicrobial Infection Successfully Salvaged With Ceftazidime-Avibactam Plus Aztreonam
Unusual clinical course, Challenging differential diagnosis, Unusual or unexpected effect of treatment
Mustafa Nuaimi ABEF 1, Jonathan Cirillo BCE 2, Sara Usbosy BEF 1, Daniel Egan BDEF 3, Amanda Kovacich ABE 2, Mario Madruga AE 1, Stephen J. Carlan
BCEF 4*
DOI: 10.12659/AJCR.952266
Am J Case Rep 2026; 27:e952266
Table 1 Clinical parameters from admission to amputation.
| Parameter | Normal values | July 10, admission | July 12, Day 2 | July 16, after AKA |
|---|---|---|---|---|
| Mean arterial pressure (mm/Hg) | 70–100 | |||
| Heart rate (BPM) | 60–100 | 68 | 98 | 95 |
| Temperature (°F) | 97–99°F | 98.1 | 99 | 97.9 |
| Pressor | Levophed | Levophed, stress dose steroid | ||
| Ventilation | Ventilator | Ventilator | Ventilator | |
| White blood cells (cells/μL) | 4500–11 000 | |||
| Hemoglobin (g/dL) | 12.3–15.3 | 8.6 | 6.6 | 8.3 |
| Platelets per microliter (μL) of blood | 150 000–450 000 | |||
| Erythrocyte sedimentation rate (mm/h) | 0–20 | 77 | ||
| C-reactive protein (mg/dL) | <1.0 | |||
| Blood urea nitrogen (mg/dL) | 7.0–20 | |||
| Creatinine (mg/dL) | 0.6–1.1 | |||
| Potassium (mEq/L) | 3.5–5.5 | 4.2 | 4.4 | 4.4 |
| HCO3 (mEq/L) | 22–26 | 22 | 20 | 19 |
| Calcium (mg/dL) | 8.5–10.5 | |||
| Aspartate transaminase (AST) (U/L) | 8–48 | |||
| Alanine transaminase (ALT) (U per liter) | 7–55 | 30 | ||
| Lactate (mmol/L) | 0.5–2.0 | 2 | ||
| . mm – millimeters; mm/hr – millimeters per hour; Hg – mercury; mg/dL – milligrams per deciliter; BPM – beats per minute; mEq/L – milliequivalents per liter; °F – degrees Fahrenheit; U/L – units per liter; μL – microliter; IU/L – International units per liter; g/dL – grams per deciliter; mmol/L – millimoles per liter. | ||||