The effectiveness of nitrofurantoin, fosfomycin and trimethoprim for the treatment of cystitis in relation to renal function.

OBJECTIVES: We evaluated the effect of renal function on clinical failure rates of nitrofurantoin, fosfomycin and trimethoprim for the treatment of cystitis in primary care. METHODS: Data were retrospectively obtained from 78 Dutch general practitioner (GP) practices between 2013 and 2019. Eligible episodes in patients (>11 years) were those requiring 5 days of nitrofurantoin (NF5), single-dose fosfomycin-trometamol (FT1), 3 days of trimethoprim (TMP3) for uncomplicated cystitis, or 7 days of nitrofurantoin (NF7) or trimethoprim (TMP7) for complicated cystitis. Clinical failure was defined as second antibiotic prescription for cystitis or pyelonephritis within 28 days post-prescription. Mixed effects regression analysis was used, with patient and GP practice as random effects and demography, comorbidity, and cystitis history as fixed effects. RESULTS: Adjusted odds ratios (aORs) for clinical failure per 10mL/min decrease in estimated glomerular filtration rate (eGFR) were 1.05 (95% CI: 1.01-1.09) for NF5 (n = 24,591), 0.96 (95% CI: 0.92-1.01) for FT1 (n = 5359), 0.98 (95% CI: 0.89-1.08) for TMP3 (n = 1064), 1.05 (95% CI: 1.02-1.09) for NF7 (n = 10,628) and 1.02 (95% CI: 0.93-1.14) for TMP7 (n = 831). In uncomplicated cystitis and eGFR ≥60 mL/min, clinical failures occurred in 14.6% (1895/12 980) of NF5-treated, 20.7% (266/1283) of FT1-treated (aOR versus NF5 1.37, 95% CI 1.18-1.59) and 20.8% (66/318) of TMP3-treated patients (aOR 1.42, 95% CI 1.07-1.87 versus NF5). In uncomplicated cystitis and eGFR <60 mL/min, FT1 resulted in 16.0% (39/244) and NF5 in 23.3% clinical failures (110/472), aOR: 0.61, 95% CI: 0.39-0.95). CONCLUSIONS: In eGFR ≥60 mL/min treatment with fosfomycin or trimethoprim for uncomplicated cystitis was associated with more clinical failure than treatment with nitrofurantoin, while in eGFR <60 mL/min nitrofurantoin was associated with more clinical failure than fosfomycin-trometamol. Renal function, if known, should be considered in the clinical decision-making for cystitis treatment.

Fosfomycin Etest for Enterobacteriaceae: Interobserver and interlaboratory agreement.

OBJECTIVES: The increasing use of fosfomycin requires reliable susceptibility testing in clinical practice. The reference standard, agar dilution (AD), is rarely used in routine settings. The fosfomycin Etest (BioMérieux) is frequently used, although reading MICs can be hampered by the interpretation of the growth of macrocolonies in the inhibition zone. We investigated the interobserver (IO), interlaboratory (IL), and interobserver-interlaboratory (IOIL) agreement of the fosfomycin Etest and evaluated the agreement with AD. METHODS: Etests were performed for 57 extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae of four bacterial species (Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Enterobacter cloacae) in two laboratories. Photographs of fosfomycin Etests were interpreted by four observers following manufacturer's instructions. RESULTS: Essential agreement (EA) and categorical agreement (CA) between Etest and AD were 57% and 89% (κ-value 0.68), respectively, with an underestimation of Etest interpretations compared with AD of 0.26 (95% confidence interval [CI] 0.03-0.48) 2-fold dilutions. Between Etest observations, IO-EA and -CA were reached in 82% and 94% of comparisons; IL-EA and -CA in 38% and 85% of comparisons; and IOIL-EA and -CA in 40% and 85% of comparisons, respectively. Agreement of the Etest with AD and between Etests was better for E. coli than for other species. Ignoring all macrocolonies and haze during Etest interpretation improved the agreement with AD (CA κ-value 0.80) and between Etests (CA κ-value from 0.68 to 0.81). CONCLUSIONS: In this study on 57 ESBL-producing Enterobacteriaceae, IOIL agreement was low with an EA of 40% and a CA of 85%, affected most by IL agreement and to a lesser extent by IO agreement.

[Desmopressin for nocturia in the old: an inappropriate treatment due to the high risk of side-effects?]. / Desmopressine voor de behandeling van nycturie bij ouderen: ongewenst door hoog risico op bijwerkingen?

Desmopressin, a synthetic analog of the antidiuretic hormone, is used in the treatment of enuresis nocturna in children and increasingly also in adults. Nocturia in the elderly causes sleeping disorders and is associated with a higher risk of falling and increased mortality. Desmopressin leads to a significant decrement of nocturia and consequently, a better sleep quality and is for this reason increasingly prescribed in the old. Desmopressin causes borderline hyponatremia (130-135 mmol/l) in 15% and severe hyponatremia in 5% of all adult users. Factors that predispose to hyponatremia are a higher dose, age > 65 years, a low-normal serum sodium, a high 24-hour urine volume and co-medication (thiazide diuretics, tricyclic antidepressants, serotonin-reuptake-inhibitors, chlorpromazine, carbamazipine, loperamide, Non-Steroidal-Anti-Inflammatory-Drugs). Hyponatremia is associated with headache, nausea, vomiting, dizziness, and can cause somnolence, loss of consciousness and death. We present two cases where initiation of desmopressin led to hyponatremia, requiring hospitalization. In view of the high risk of desmopressin-associated hyponatremia in the older population, alternative treatment strategies for nocturia must be considered first. If desmopressin is prescribed, strict follow-up of serum sodium levels is necessary.