Antibiotic Guide

Antibiotic Classes Quick Reference

◆ Penicillins

Mechanism: Beta-lactam — inhibit bacterial cell wall synthesis by binding penicillin-binding proteins (PBPs), leading to cell lysis.

Drug	Spectrum	Key Uses	Notes
Amoxicillin	Gram+ Some Gram−	RTI, otitis media, dental	Oral; destroyed by beta-lactamase
Amoxicillin-Clavulanate (Co-amoxiclav)	Gram+ Gram− Anaerobes	LRTI, bites, SSTI, dental abscesses	Clavulanate = beta-lactamase inhibitor; risk of cholestatic jaundice
Piperacillin-Tazobactam (Pip-Tazo)	Gram+ Gram− Anaerobes Pseudomonas	Sepsis, HAP/VAP, intra-abdominal, febrile neutropenia	Broad spectrum; extended infusion 4h for PK/PD benefit
Benzylpenicillin (Pen G)	Gram+ Streptococci, Neisseria	Meningococcal disease, strep throat, syphilis	IV only; narrow spectrum; very cheap
Flucloxacillin	Staph aureus (MSSA)	Skin & soft tissue, osteomyelitis, endocarditis (MSSA)	Penicillinase-resistant; oral/IV; take on empty stomach

◆ Cephalosporins

Mechanism: Beta-lactam — same as penicillins. Higher generations have broader Gram-negative activity. Cross-reactivity with penicillins ~1-2% (true allergy).

Generation	Drug(s)	Coverage	Key Uses
1st	Cefalexin (oral), Cefazolin (IV)	Gram+ (MSSA, Strep)	Surgical prophylaxis, skin/soft tissue, UTI
2nd	Cefuroxime	Gram+, improved Gram−	RTI, UTI, surgical prophylaxis
3rd	Ceftriaxone, Ceftazidime	Broad Gram−; Ceftazidime covers Pseudomonas	CAP, meningitis, pyelonephritis; Ceftazidime for Pseudomonas/HAP
4th	Cefepime	Gram+, Gram− including Pseudomonas	Febrile neutropenia, HAP, severe infections
5th	Ceftaroline	MRSA (anti-MRSA activity)	MRSA SSTI, CAP; reserve use; no Pseudomonas

◆ Carbapenems — Reserve Agents

Reserve antibiotics: Use only for MDR Gram-negative infections, failed standard therapy, or high-risk patients. Overuse drives carbapenem resistance (CRE).

Drug	Coverage	Key Uses	Notes
Meropenem	Broadest — Gram+, Gram−, Pseudomonas, anaerobes	CRE-excluding MDR Gram−, severe sepsis, meningitis	CNS penetration; preferred in ICU
Imipenem-Cilastatin	Similar to Meropenem	Polymicrobial, intra-abdominal	Cilastatin prevents renal metabolism; lower seizure threshold
Ertapenem	Gram+, Gram−, anaerobes; NO Pseudomonas	ESBL organisms, complicated UTI, community-acquired IAI	Once-daily dosing; outpatient-friendly

◆ Fluoroquinolones

Cautions: QT prolongation, tendinopathy/tendon rupture (especially with steroids/elderly), CNS effects, C.diff risk. Avoid in pregnancy.

Ciprofloxacin: UTI, GI infections, bone/joint, Pseudomonas infections
Levofloxacin: CAP, sinusitis, UTI, atypical organisms; broader Gram+ than cipro
Mechanism: Inhibit DNA gyrase & topoisomerase IV
Avoid dairy/antacids within 2h (chelation)
Sun sensitivity — counsel patients

◆ Macrolides

Azithromycin: Atypical pneumonia (Mycoplasma, Chlamydia, Legionella), STIs, Chlamydia trachomatis, MAC prophylaxis in HIV
Clarithromycin: H. pylori eradication (triple therapy), RTI, MAC
Mechanism: 50S ribosomal subunit inhibition (bacteriostatic)
QT prolongation — ECG if risk factors
Drug interactions via CYP3A4 (Clarithromycin strong inhibitor)

◆ Aminoglycosides

TDM Essential: Nephrotoxicity and ototoxicity — monitor levels, renal function daily.

Gentamicin: Serious Gram-negative sepsis, synergy with beta-lactams for Gram+ endocarditis
Amikacin: MDR Gram-negatives resistant to Gentamicin; broader activity
Mechanism: 30S ribosomal subunit — bactericidal; concentration-dependent killing
Once-daily dosing (Hartford nomogram) preferred — reduces toxicity
Avoid in renal impairment unless essential

◆ Glycopeptides

TDM Required: Vancomycin AUC/MIC-guided dosing. Target AUC 400–600 mg·h/L.

Vancomycin: MRSA, C. difficile (oral for C.diff), Gram+ allergy alternatives
Teicoplanin: MRSA, fewer infusion reactions than vancomycin; once-daily after loading
Mechanism: Inhibit cell wall by binding D-Ala-D-Ala precursor
Oral Vancomycin = NOT absorbed systemically (C.diff only)
Red man syndrome: NOT allergy — slow infusion, antihistamine

◆ Metronidazole

Anaerobes (Bacteroides, Clostridium)
C. difficile (mild-moderate)
Protozoal infections: Giardia, Trichomonas, Entamoeba
Take with food (reduces GI side effects)
Avoid alcohol (disulfiram-like reaction)
Metallic taste — counsel patients

◆ Linezolid & Polymyxins

Linezolid: MRSA (alternative to vancomycin), VRE; Mechanism: 50S (oxazolidinone); Watch: serotonin syndrome (SSRIs), myelosuppression (weekly FBC), MAO inhibition
Colistin (Polymyxin E): Last resort for MDR Gram-negatives (CRE, MDR Pseudomonas, Acinetobacter); IV & nebulised; nephrotoxic — monitor renal function; TDM where available

Linezolid + SSRIs/Tramadol: Risk of serotonin syndrome — check medication list before prescribing.

Vancomycin TDM Calculator

◆ AUC/MIC-Guided Vancomycin Check

Estimated AUC calculation using single-point Bayesian approach approximation. For clinical decision support — always confirm with pharmacist.

Total Daily Dose (mg)

Dosing Interval (hours)

Trough Level (mg/L)

MIC (mg/L)

Enter values above and click Calculate.

Target AUC/MIC: 400–600 mg·h/L For serious MRSA infections. AUC <400 = under-dosing (treatment failure risk). AUC >600 = nephrotoxicity risk. Trough-based target: 15–20 mg/L for serious MRSA (older method).

Community-Acquired Pneumonia (CAP)

Severity	Setting	Regimen	Duration
Mild	Outpatient / ward	Amoxicillin 500mg–1g TDS ± Azithromycin 500mg OD (atypical cover)	5–7 days
Moderate	Ward (HDU-level)	Levofloxacin 500mg BD or Ceftriaxone 1–2g IV OD + Azithromycin 500mg IV/oral OD	5–7 days
Severe / ICU	ICU / intubated	Pip-Tazo 4.5g IV q6h (extended infusion) + Azithromycin IV or Levofloxacin IV ± Oseltamivir (if influenza suspected)	7 days (no benefit of longer)

CURB-65 score: Confusion, Urea >7, RR ≥30, BP <90/60, Age ≥65. Score 0–1 = outpatient, 2 = hospital, ≥3 = ICU consider. Severity guides antibiotic choice.

Healthcare-Associated Pneumonia (HAP / VAP)

Risk Level	Regimen	Notes
Standard HAP	Pip-Tazo 4.5g q6h IV or Cefepime 2g q8h IV	Cover Gram-negatives including Pseudomonas
MRSA risk (prior MRSA, skin breakdown, HD, recent IV antibiotics)	Add Vancomycin IV (AUC-targeted) or Linezolid 600mg BD	Review cultures at 48–72h, de-escalate
Aspiration / anaerobic risk	Add Metronidazole 500mg TDS IV/oral	Poor dentition, witnessed aspiration, lung abscess
MDR-risk / prior carbapenem use	Meropenem 1–2g q8h ± Polymyxin if CRE suspected	Review local susceptibility data; ID team input

HAP/VAP Duration: 7 days — evidence shows no benefit of 14 days (JAMA 2006). Reassess daily. Procalcitonin-guided de-escalation reduces duration.

Urinary Tract Infections (UTI)

Type	Regimen	Duration	Key Points
Uncomplicated UTI (female)	Trimethoprim 200mg BD or Nitrofurantoin 100mg MR BD	3 days (Trimethoprim), 5 days (Nitrofurantoin)	Check local resistance; Trimethoprim avoid if resistant >20% locally
Complicated UTI / male	Trimethoprim 200mg BD or Cefalexin 500mg TDS	7 days	Mid-stream urine (MSU) before starting
Pyelonephritis	Ceftriaxone 1–2g IV OD, step-down to Cefalexin/Co-amoxiclav oral when afebrile 24h	Total 10–14 days	Blood cultures before antibiotics; renal ultrasound if no improvement 48–72h
Catheter-Associated UTI (CAUTI)	Treat ONLY if symptomatic (fever, rigors, new confusion). Bacteriuria alone = do NOT treat	7 days symptomatic	Change catheter if possible; consider removal

Sepsis — Unknown Source

Sepsis Bundle (Hour-1): Blood cultures x2, lactate, IV access, 30 mL/kg crystalloid if hypotensive, ANTIBIOTICS WITHIN 1 HOUR of recognition.

Risk Profile	Empirical Regimen	Rationale
Community-acquired, no MDR risk	Pip-Tazo 4.5g q6h IV + Vancomycin IV (AUC-targeted)	Covers Gram+/Gram−/Pseudomonas + MRSA
Healthcare/hospital-acquired, MDR risk	Meropenem 1–2g q8h IV + Vancomycin IV	MDR Gram-negatives; MRSA cover
Neutropenic sepsis	Pip-Tazo 4.5g q6h IV or Cefepime 2g q8h IV ± Vancomycin	Anti-pseudomonal cover essential
Abdominal source	Pip-Tazo (anaerobic cover included) or Meropenem + Metronidazole	Gram+ + Gram− + anaerobic triple cover

De-escalation at 48–72h: Review cultures and narrow antibiotic spectrum. Stopping unnecessary agents reduces resistance and side effects.

Skin & Soft Tissue Infections (SSTI)

Condition	Likely Pathogen	Regimen	Duration
Cellulitis / Erysipelas	Strep. pyogenes, MSSA	Flucloxacillin 1g IV/oral QDS or Cefalexin 500mg QDS oral	5–7 days (up to 14 if severe)
Abscess	MSSA/MRSA	Incision & drainage (primary); add Flucloxacillin; Vancomycin if MRSA risk	5 days post-drainage
MRSA SSTI	MRSA	Vancomycin IV + Linezolid (severe); Doxycycline or TMP-SMX oral (mild)	7–14 days depending on depth
Necrotising fasciitis	Mixed/Group A Strep + anaerobes	Meropenem + Clindamycin (anti-toxin) + Vancomycin; URGENT SURGICAL DEBRIDEMENT	Until source controlled + afebrile
Diabetic foot infection	Mixed — Gram+/Gram−/Anaerobes	Pip-Tazo IV or Amoxicillin-Clavulanate + Metronidazole	7–14 days; longer if bone involved

GCC-Specific: MERS-CoV Protocol

MERS-CoV (Middle East Respiratory Syndrome): GCC endemic. No proven antiviral. Manage supportively. Strict droplet + contact + airborne precautions. Notify public health immediately.

Antivirals (experimental): Ribavirin + Interferon alfa-2b — limited evidence; use per local protocol/ID consult
Antibiotics: Only for confirmed secondary bacterial co-infection; do NOT give prophylactic antibiotics
PPE: N95 respirator, eye protection, gown, gloves; airborne isolation room (negative pressure preferred)
Notify infection control, public health authority, and ministry of health (DHA/MOH mandate)
Camel exposure history (drinking raw camel milk, animal contact) — relevant epidemiological risk factor

Clostridioides difficile (C. diff)

Severity	Criteria	Treatment	Duration
Mild/Moderate	WBC <15, Creatinine normal, afebrile	Oral Metronidazole 400–500mg TDS	10 days
Severe	WBC ≥15, Creatinine ≥1.5x baseline, temp >38.5°C	Oral Vancomycin 125mg QDS (NOT IV — not absorbed)	10 days
Fulminant/Complicated	Ileus, megacolon, hypotension	Oral/rectal Vancomycin + IV Metronidazole; surgical consult	Until clinically resolved
Recurrent (2nd episode)	Second episode within 12 weeks	Fidaxomicin 200mg BD (preferred) or tapered Vancomycin	10 days Fidaxomicin

Contact precautions: Soap and water ONLY — alcohol hand gel does NOT kill C. diff spores. Dedicate equipment. Side room essential.

Interpreting Culture & Sensitivity Reports

MIC & Susceptibility Classification

MIC (Minimum Inhibitory Concentration): Lowest concentration of antibiotic that inhibits visible bacterial growth (mg/L)
S — Susceptible: Infection likely to respond to standard dosing
I — Intermediate: May respond with higher dose or at sites of antibiotic concentration (e.g. urine); also called "Susceptible-Dose Dependent" (SDD) per EUCAST 2019
R — Resistant: Unlikely to respond even at maximum dose; avoid

Antibiotic Selection Process

1. Confirm species (e.g. E. coli, Klebsiella, Staph aureus)
2. Review sensitivities — choose narrowest effective agent
3. Consider site of infection — antibiotic must reach the site
4. Consider patient allergies and renal/hepatic function
5. De-escalate from empirical broad-spectrum to narrow-spectrum based on culture
6. Document rationale in notes; inform prescriber of results promptly

AMS Core Principles & Nurse's Role

◆ The Right Antibiotic

Verify drug, dose, route, frequency, and duration match indication
Check allergy status before every administration
Confirm cultures were taken before first dose (where applicable)
Question empirical broad-spectrum use beyond 72h without documented indication

◆ Monitor & Report

Check TDM results (Vancomycin, Gentamicin) and report to prescriber
Review daily: culture results, WBC, CRP, temperature trending
Document antibiotic start date and planned stop/review date
Report antibiotic-associated diarrhoea (consider C. diff)
Report any adverse effects (rash, nephrotoxicity, hepatotoxicity)

◆ De-escalation

Review sensitivities daily once culture results available
If organism is susceptible to narrow-spectrum agent — advocate de-escalation
Document clinical status at Day 3 review
If MRSA PCR/culture negative — consider stopping Vancomycin
Remind team of planned stop date on drug charts/electronic records

◆ IV to Oral Switch

Switch criteria (all must be met):
• Tolerating oral fluids/medications
• Afebrile for ≥24 hours
• Haemodynamically stable (no vasopressors)
• WBC trending to normal
• Suitable oral equivalent available with good bioavailability
High oral bioavailability (>80%): Amoxicillin, Levofloxacin, Metronidazole, Co-amoxiclav, Linezolid, Trimethoprim

Antibiotic Allergy Assessment

Key Fact: 90% of patients labelled "Penicillin Allergic" are NOT truly allergic. Most have experienced intolerance or non-allergic reactions. Incorrect allergy labels drive use of broader/less effective antibiotics and contribute to resistance.

Category	Definition	Examples	Action
True Allergy	IgE-mediated or immune-mediated reaction	Anaphylaxis, urticaria, angioedema, SJS	Document clearly; avoid drug class; refer for allergy testing if clinically needed
Intolerance	Predictable pharmacological side effect	Nausea, diarrhoea, yeast infection	Not a true allergy — document as intolerance; antibiotic may still be used if clinically essential
Side Effect	Non-immune-mediated reaction	Metallic taste (Metronidazole), headache	Not an allergy; document correctly

De-labelling Process:

Structured allergy history by nurse/pharmacist
Identify type and timing of original reaction
Refer to allergy clinic for skin testing (penicillin SPT/IDT)
Oral challenge under supervision if SPT negative
Update allergy record if de-labelled

Cephalosporin Cross-Reactivity: True cross-reactivity with Penicillin ~1–2% (side chain dependent, not ring-structure). Most patients with penicillin allergy can safely receive cephalosporins. Consult pharmacist or ID if uncertain.

Duration Guidelines

Infection	Recommended Duration	Notes
CAP (mild-moderate)	5–7 days	5 days sufficient if good response (IDSA/ATS); procalcitonin-guided
HAP/VAP	7 days	RCT evidence — 8 days = 15 days outcomes (non-inferior except Pseudomonas)
UTI (uncomplicated female)	3–5 days	3 days Trimethoprim; 5 days Nitrofurantoin
Pyelonephritis	10–14 days	Shorter if fluoroquinolone used (7 days); IV until afebrile then oral
SSTI (cellulitis)	5–7 days	Reassess at 5 days; extend if not improving
Sepsis (bacteraemia)	7–14 days	Depends on source; S. aureus bacteraemia minimum 14 days (IV); Gram-neg 7–10 days
C. difficile	10 days	Fidaxomicin for recurrent; extended taper for multiple recurrences
Osteomyelitis	4–6 weeks	IV then oral; OPAT (outpatient parenteral antibiotic therapy) often required

GCC Context — Resistance & Mandates

◆ Local Resistance Landscape

High rates of ESBL-producing E. coli & Klebsiella in UAE, KSA, Qatar
MRSA prevalence 20–30% of S. aureus isolates in GCC ICUs
Carbapenem-resistant Enterobacterales (CRE) emerging — NDM-1 (New Delhi Metallo-beta-lactamase) detected
High fluoroquinolone resistance in Gram-negatives (overuse historically)
MERS-CoV remains endemic in Arabian Peninsula — strict protocols

◆ Regulatory & JCI Standards

DHA (Dubai Health Authority) / MOH UAE: Antimicrobial stewardship mandatory for all licensed facilities; AMS committee required
MOH KSA / MNGHA: National AMS programme guidelines; formulary restrictions for reserve antibiotics
JCI Standard MM.04: Medication management — high-alert medications including vancomycin require double-check protocols
Restricted antibiotics: Carbapenems, Colistin, Linezolid, Ceftaroline — require ID/AMS team approval in most GCC hospitals
Mandatory reporting: MRSA, VRE, CRE, C. difficile to infection control

Broad-Spectrum Antibiotics — Document & Review: When prescribing or administering broad-spectrum agents (Carbapenems, Pip-Tazo, Vancomycin, Colistin), document: indication, planned duration, and 48–72h review date. Failure to de-escalate within 72h without reason should trigger AMS pharmacist review.

IV Antibiotic Administration

Antibiotic	Infusion Time	Rate / Volume	Key Admin Notes
Piperacillin-Tazobactam (Pip-Tazo)	4 hours (extended infusion)	Dilute in 250 mL NaCl 0.9%	PK/PD advantage: time-dependent killing; extended infusion increases time above MIC ≥16 mg/L; stable 4h at room temp
Vancomycin	60 min per 1,000 mg minimum	Max 10 mg/min; dilute to 5 mg/mL (250 mg in 50 mL)	Too-fast infusion = Red Man Syndrome; use dedicated lumen; flush line before/after
Meropenem	30 min (standard); 3h extended for resistant organisms	Dilute in 50–100 mL NaCl 0.9%	Stable only 1h at room temp in NaCl; reconstitute freshly; CNS side effects if renal dose not adjusted
Gentamicin (once-daily)	60 min	Dilute in 100 mL NaCl 0.9%	Concentration-dependent; once-daily reduces toxicity; use Hartford nomogram for dose adjustment
Ceftriaxone	30 min	1–2g in 50–100 mL NaCl 0.9%	DO NOT mix with calcium-containing solutions (precipitation); incompatible with Ringer's lactate in neonates
Metronidazole IV	30–60 min	500 mg in 100 mL (pre-mixed) or dilute in NaCl 0.9%	Light-sensitive; avoid rapid infusion; avoid extravasation
Linezolid	30–120 min	600 mg in 300 mL pre-mixed bag	Protect from light; check drug interactions (SSRIs, MAOIs, Tramadol) before giving
Colistin (Polymyxin E)	30–60 min	Dilute in NaCl 0.9%; given as pro-drug (CMS)	Nephrotoxic — monitor renal function daily; dose in units not mg; specialist supervision required

Red Man Syndrome

NOT an allergic reaction — Red Man Syndrome is a rate-related infusion reaction to Vancomycin (direct mast cell degranulation, non-IgE mediated).

Signs & Symptoms

Flushing of face, neck, upper torso ("red man")
Pruritus / itching
Hypotension (if severe)
Erythematous rash / maculopapular rash over upper body
Usually appears 5–10 min into infusion

Management

STOP or slow infusion immediately
Administer IV Antihistamine (Chlorphenamine 10 mg slow IV)
Once settled — restart at HALF the rate
Pre-medicate with antihistamine 30 min before future doses if recurrent
Document as infusion reaction — NOT as allergy on allergy record
Inform prescriber; consider dose review

Therapeutic Drug Monitoring (TDM)

◆ Gentamicin TDM — Hartford Nomogram (Once-Daily)

Sample Times (Once-Daily 7 mg/kg):

Peak: 1 hour post end of infusion — Target: 5–10 mg/L (serious infection)
Trough: 30 min before next dose — Target: <1 mg/L (renal safety)
Nomogram sample: 6–14h post-infusion, plot on Hartford nomogram to determine q24/q36/q48h interval

Toxicity Monitoring:

Nephrotoxicity: rising creatinine/falling eGFR — check daily U&E
Ototoxicity: tinnitus, hearing loss, vertigo — ask patient daily
Avoid concurrent nephrotoxins: NSAIDs, contrast, Amphotericin B
If trough >1 mg/L — withhold dose, inform prescriber, recheck

◆ Vancomycin TDM

Target / Parameter	Value	Rationale
AUC/MIC target (preferred method)	400–600 mg·h/L	Optimal bactericidal activity vs toxicity; Bayesian-guided dosing
Trough (alternative/trough-only method)	10–20 mg/L (serious MRSA: 15–20)	Older method; AUC preferred per ASHP/IDSA 2020 guidelines
When to draw trough	30 min before 4th–5th dose (steady state)	Earlier sampling inaccurate until steady state reached
Supratherapeutic (trough >20 mg/L)	Hold dose, recheck level, reduce dose or extend interval	Nephrotoxicity risk increases significantly
Subtherapeutic (trough <10 mg/L)	Increase dose, discuss with pharmacist	Risk of treatment failure; MIC creep / resistance

Oral Antibiotic Counselling

Antibiotic	Food Interaction	Other Counselling Points
Metronidazole	Take WITH food	Avoid alcohol entirely during course + 48h after (disulfiram reaction); metallic taste expected
Nitrofurantoin	Take WITH food	Urine may turn brown/dark — reassure patient; avoid in renal impairment (eGFR <45)
Flucloxacillin	Take 30 min BEFORE food	Food reduces absorption significantly; complete full course
Doxycycline	Take WITH food (reduces GI)	Avoid direct sunlight (photosensitivity); avoid lying down 30 min after dose (oesophagitis); avoid dairy within 2h
Tetracyclines (general)	Avoid dairy, antacids, iron supplements within 2h	Chelation reduces absorption; photosensitivity; teeth discolouration in children — avoid under 8 years
Fluoroquinolones (oral)	Avoid antacids/dairy/iron within 2h before or 6h after	Sun protection; avoid prolonged use; tendon warning (especially elderly + steroids)
Amoxicillin / Co-amoxiclav	Can take with or without food	Complete full course; report rash (may be drug-induced, not true allergy); co-amoxiclav — liver monitoring if prolonged
Azithromycin	Capsules: empty stomach. Tablets: can be with food	Once-daily; 5-day course typical; GI side effects common; report palpitations (QT risk)

Anaphylaxis Readiness

Anaphylaxis Protocol: Be prepared before administering ANY IV antibiotic for the first time — especially beta-lactams in documented allergy patients.

Pre-Administration Checklist

☑ Confirm allergy status — check drug chart AND EMR allergy record
☑ Adrenaline (Epinephrine) 1:1000 drawn up and bedside OR adrenaline auto-injector accessible
☑ Emergency trolley location known
☑ Patient in bed or chair for first dose observation
☑ IV access patent — flush before administration
☑ Observe patient continuously for first 15–30 min of infusion

Anaphylaxis Recognition & Action

Signs: urticaria/rash, angioedema, bronchospasm (wheeze), hypotension, tachycardia, loss of consciousness
STOP antibiotic immediately
Call for help / crash team
Position: lying flat, legs elevated (unless breathing compromised)
Adrenaline 0.5 mg IM (0.5 mL of 1:1000) into outer mid-thigh
IV fluid resuscitation: 500 mL–1L NaCl 0.9% stat
Oxygen high-flow 15L via non-rebreathe mask
Antihistamine (Chlorphenamine 10 mg IV) + Hydrocortisone 200 mg IV after adrenaline

MRSA — Methicillin-Resistant Staphylococcus aureus

ESBL — Extended-Spectrum Beta-Lactamase Producers (E. coli / Klebsiella)

CRE/CPE — Carbapenem-Resistant Enterobacterales

MDRP — MDR Pseudomonas aeruginosa

Clostridioides difficile — C. diff