Positive urinary antigen tests for Streptococcus pneumoniae in community-acquired pneumonia: a 7-year retrospective evaluation of health care cost and treatment consequences

Abstract

A positive pneumococcal urinary antigen test (PUAT) for Streptococcus pneumoniae allows an early switch from empiric to targeted treatment in hospitalised community-acquired pneumonia (CAP) patients. The economic and treatment consequences of this widespread implemented test are, however, unknown. We retrospectively evaluated all tests performed since its introduction in two teaching hospitals. Data on patient characteristics, treatment, admission and outcome were retrieved from the electronic patient files. Test benefits were expressed as the number of days that targeted therapy (i.e. penicillin) was administered to hospitalised CAP patients due to a positive PUAT. This calculation was based on the timing of the PUAT and the initiation of targeted therapy. Subsequently, we performed two direct cost analyses from a hospital perspective, first including tests performed for CAP only, and second including costs of all (excessive) tests. Between 2005 and 2012, 3,479 PUATs were performed, of which 1,907 (55 %) were for CAP. A total of 1,638 PUATs (86 %) were negative and 269 (14 %) were positive. Fifty-two (19 %) positive tests were excluded. In 75 (35 %) of the 217 remaining positive tests, a positive PUAT led to targeted treatment during 293 cumulative admission days. Testing costs for CAP only were €131 per targeted treatment day. These costs were €257 if local protocol dictated PUAT use for all CAP cases, as opposed to €72 if the test was reserved for severe cases only. When including all tests, PUAT costs were €254 per targeted treatment day. Therefore, improving the selective use of the PUAT in hospitalised CAP patients may lead to increased (cost-)efficiency.

Predicting pneumococcal community-acquired pneumonia in the emergency department

“…In a study using the ICA as a treatment decision strategy, amoxycillin was prescribed to 48 of 219 patients with CAP on the basis of ICA results, and appeared to be as effective as clarithromycin in all other patients [22]. In two other observational studies, only 31.5% and 35% of the patients with positive ICA results switched to (more) targeted antibiotic treatment [23,24]. N, number of patients with cut-off value above the set limit; NPV, negative predictive value; PPV, positive predictive value.…”

Evaluating the utility of Binax NOW Streptococcus pneumoniae urinary antigen test in adults with community acquired pneumonia in China

“…Among the five patients with "false-positive", Klebsiella was identified in one patient's sputum sample and rhinovirus was confirmed by RT-PCR in another. 14, 24 Oosterheert pointed out the cost reduction depended on the expense of empirical treatment and the proportion of evaluable and positive test. Low sensitivity of sputum culture, possibility of colonization, 18 persistence of antigen excretion, 19 and vaccination 20 were also the possible reasons for "false-positive".…”

“…23 Piso and Engel also did not recommend the routine use of the ICT in the setting of CAP, because of the low sensitivity in negative blood culture patients and limited ecological benefits. 14,24 Oosterheert pointed out the cost reduction depended on the expense of empirical treatment and the proportion of evaluable and positive test. 25 The proportion of positive test in our study was much lower than researches from other countries (3.3% vs 29%-35.5%), in spite of the sensitivity was similar to theirs (52%-65.9%) when qualified sputum culture was regarded as the gold-standard.…”

Neumonía adquirida en la comunidad

“…En consecuencia, a lo sumo, no podemos más que esperar beneficios relativos a una reducción en el espectro antibacteriano del tratamiento y de los efectos secundarios asociados al mismo, pero no beneficios en términos de supervivencia. Además, el precio del test es superior al de las pautas antibióticas empleadas y un cálculo del balance coste-beneficio resulta negativo, máxime si, como sucede en muchos centros, se utiliza indiscriminadamente 1,50 .…”