Many rapid diagnostic tests, such as PCR, are in early development, not commonly available, or not sufficiently reliable [66]. PCR testing for detection of Mycobacterium tuberculosis is the only PCR test for detection of a respiratory tract pathogen that has been cleared by the US Food and Drug Administration (FDA), but it is recommended for use only with specimens that contain AFB on direct smears. Diagnostic procedures that provide identification of a specific etiology within 24 72 h can still be useful for guiding continued therapy.

The etiologic diagnosis can be useful for both prognostic and therapeutic purposes. Once a diagnosis has been established, the failure to respond to treatment can be dealt with in a logical fashion based on the causative organism and its documented antibiotic susceptibility, rather than by empiric selection of antimicrobial agents with a broader or different spectrum. Furthermore, if a drug reaction develops, an appropriate substitute can be readily selected.

Performance of blood cultures within 24 h of admission for CAP is associated with a significant reduction in 30-day mortality [67]. With regard to sputum bacteriology, several studies have suggested that mortality associated with CAP in hospitalized patients is the same for those with and without an etiologic diagnosis [68 70]. These studies were not specifically designed to test the hypothesis. Instead, the conclusion is based on retrospective analyses of cases with and without an etiologic diagnosis. Other outcomes also of interest that have not been assessed are length of stay, cost, resource use, and morbidity.

Some studies, although uncontrolled, do suggest benefit of these diagnostic studies [71 76]. For example, Boerner and Zwadyk [64] reported that a positive early diagnosis by sputum Gram staining correlated with more rapid resolution of fever after initiation of antimicrobial therapy. An additional study by Torres et al. [76] showed that inadequate antibiotic treatment was clearly related to poor outcomes, which suggests that the establishment of an etiologic diagnosis is important.

The frequency of microbiological studies for CAP patients is highly variable. A report from the Pneumonia PORT study, with analysis of 1343 hospitalized patients during 1991 1994, showed that the frequencies of sputum Gram staining and sputum culture within 48 h of admission were 53% and 58%, respectively [77]. These studies were done on only 8% 11% of 944 outpatients with CAP.
Participating centers in this and most other published studies of CAP are academic institutions at which microbiological studies are probably more frequent than in other health care settings. The finding of a likely pathogen in blood cultures averages 11% in published reports concerning hospitalized patients with CAP [9]. The yield with sputum studies is highly variable, ranging from 29% to 90% for hospitalized patients and usually <20% for outpatients [2, 26, 28, 36, 41, 67, 75 77]. The large variation among studies is presumably explained by variations in the quality of microbiological analyses, epidemiological patterns, and the patient population served.

It is our consensus that establishment of an etiologic diagnosis, with performance of blood cultures before initiation of antimicrobial treatment (A-I) and sputum Gram staining and culture (B-II), has value for patients who require hospitalization. The goal is to establish a specific diagnosis that can be used for more precise and often more cost-effective use of antimicrobial agents. On the other hand, the utility of diagnostic studies for CAP of less severity (not requiring hospitalization) is unclear. More studies are needed to verify the significance of diagnostic studies in these cases.

Etiologic diagnosis. Confidence in the accuracy of the diagnosis depends on the pathogen and on the diagnostic test, as follows.

1. Diagnosis definite: a definite etiology is established by a compatible clinical syndrome plus the recovery of a probable etiologic agent from an uncontaminated specimen (blood, pleural fluid, transtracheal aspirate, or transthoracic aspirate) or the recovery from respiratory secretions of a likely pathogen that does not colonize the upper airways (e.g., M. tuberculosis, Legionella species, influenza virus, or P. carinii; table 10) (A-I). Some serological tests are regarded as diagnostic, although the results are usually not available in a timely manner or the diagnostic criteria are controversial.

1. 2. Diagnosis probable: a probable etiologic diagnosis is established by a compatible clinical syndrome with detection (by staining or culture) of a likely pulmonary pathogen in respiratory secretions (expectorated sputum, bronchoscopic aspirate, or quantitatively cultured bronchoscopic bronchoalveolar lavage [BAL] fluid or brush catheter specimen). With semiquantitative culture, the pathogen should be recovered in moderate to heavy growth (B-II).
   
   

Tests or specimens used for etiologic diagnosis. The following tests or types of specimens are used to establish an etiologic diagnosis.

1. Body fluids: blood culture specimens (with 2 needlesticks performed at separate sites) should be obtained from patients who require hospitalization for acute pneumonia (A-I). Potentially infected body fluids from other anatomic sites, including pleural fluid, joint fluid, and CSF, should have Gram staining and culture if warranted by the clinical presentation.
   
2. 2. Sputum examination (table 8 and figure 2): the value of Gram staining of expectorated sputum is debated [60, 62, 63, 68 70, 75 80], but we recommend this relatively simple, inexpensive procedure for guiding initial selection of antimicrobial therapy, provided that a deep-cough specimen is obtained before antibiotic therapy, rapidly transported, and properly processed in the laboratory within a few hours of collection (B-II). Therapy with antimicrobial agents should not be delayed for acutely ill patients because of the difficulty in obtaining specimens for microbiological studies. Routine laboratory tests should include Gram staining, cytological screening, and aerobic culture of specimens that satisfy cytological criteria.
   Cytological criteria for judging the acceptability of specimens include the relative number of polymorphonuclear cells (PMN) and squamous epithelial cells (SEC) in patients with normal or elevated WBC counts, determined with use of a low-power-field examination (LPF); the acceptable values range from >25 PMN+ < 10 SEC/LPF to <25 SEC/LPF, based on correlation of culture results with clinical findings and results of transtracheal aspiration (A-I) [81, 82]. Some authorities recommend a criterion of >10 WBC per SEC. Mycobacteria and Legionella species are exceptions, since microscopic criteria may yield misleading results.
   Cultures should be performed rapidly [83], although the consequence of time delays in processing is disputed [84]. Interpretations of expectorated sputum cultures should include clinical correlations and semiquantitative results. In office practice, it may not be realistic to perform Gram staining in a timely manner to guide antibiotic decisions, but a slide may be prepared, air-dried, and heat-fixed for subsequent interpretation (C-III).
   Numerous studies support the use of routine microscopic examination of a gram-stained sputum sample, with recognition of lancet-shaped gram-positive diplococci that suggest S. pneumoniae. Most show the sensitivity of sputum Gram staining for patients with pneumococcal pneumonia to be 50% 60% and the specificity to be >80% [60, 63 65, 75]. In a prospective study of 144 patients admitted to the hospital with CAP, 59 (41%) had a valid specimen obtained, with the cytological criteria of >25 PMN and <10 SEC evident on low-power magnification. The gram-stained smears of 47 valid specimens by these criteria showed a predominant bacterial morphotype that predicted the blood culture isolate in 40 (85%) valid specimens; physicians could have selected appropriate antimicrobial therapy for >90% of patients on the basis of gram-staining results [75].
   
   In haemophilus pneumonia, the Gram stain reading is even more reliable because of the profuse number of organisms that are regularly present. The finding of many WBC with no bacteria in a patient who has not already received antibiotics can reliably exclude infection by most ordinary bacterial pathogens. The validity of the gram-stain reading, however, is directly related to the experience of the interpreter [85].
   
   Routine cultures of expectorated sputum are neither sensitive nor specific when the common bacteriologic methods of many laboratories are used. The most likely explanation for unreliable microbiological data is that the specimen did not provide a rich enough source of inflammatory material from the lower respiratory tract, either because the patient was unable to cough up a reliable specimen or because the health care provider did not give sufficient priority to obtaining such a specimen. Other reasons include prior administration of antibiotics, delays in processing the specimen, insufficient attention to separating sputum from saliva before streaking slides or culture plates, and difficulty with interpretation because of the contamination by the flora of the upper airways.
   
   The flora may include potential pathogens (leading to false-positive cultures), and the normal flora often overgrow the true pathogen (leading to false-negative cultures), especially with fastidious pathogens such as S. pneumoniae. In cases of bacteremic pneumococcal pneumonia, S. pneumoniae may be isolated in sputum culture in only 40% 50% of cases when standard microbiological techniques are used [86, 87]. The yield of S. pneumoniae is substantially higher from transtracheal aspirates [88 91], transthoracic needle aspirates [89, 92], and quantitative cultures of BAL aspirates [89, 93]. Prior antibiotic therapy may reduce the yield of common respiratory pathogens in cultures of respiratory tract specimens from any source and is often associated with false-positive cultures for upper airway contaminants, such as gram-negative bacilli or S. aureus [62, 89].
   
3. Induced sputum: the utility of these specimens for detecting pulmonary pathogens other than P. carinii or M. tuberculosis is poorly established.
4. Serological studies: these tests are usually not helpful in the initial evaluation of patients with CAP (C-III) but may provide data useful for epidemiological surveillance. Cold agglutinins in a titer 1 : 64 support the diagnosis of M. pneumoniae infection, with a sensitivity of 30% 60%, but this test has poor specificity. IgM antibodies to M. pneumoniae require up to 1 week to reach diagnostic titers; reported results for sensitivity are variable [94, 95]. The serological responses to Chlamydia and Legionella species take even longer [96, 97]. The acute antibody test for Legionella in legionnaires' disease is usually negative or demonstrates a low titer [98, 99]. Some authorities have accepted an acute titer 1 : 256 as a criterion for a probable or presumptive diagnosis, but 1 study showed that this titer had a positive predictive value of only 15% [99]. If serological tests are to be used, an acute-phase serum specimen must be obtained from selected patients. Then, if the etiology of a case remains in question, a convalescent-phase serum can be obtained, and serological studies of paired sera can be performed. This method to identify causative agents is primarily for epidemiological information. These data indicate that there are no commonly available serological tests that can be used to accurately guide therapy for acute infections caused by M. pneumoniae, C. pneumoniae, or Legionella (D-III).
5. Antigen detection: antigen-detection methods for identification of microorganisms in sputum and in other fluids have been studied for >70 years with a variety of techniques counter-immunoelectrophoresis, latex agglutination, immunofluorescence, and enzyme immunoassay (EIA). Although their use for identification of bacterial agents (i.e., S. pneumoniae) has been favored in many European centers, they have been less acceptable to North American laboratories. Cost, time requirements, and relative lack of sensitivity and specificity (depending on the method) are potential limitations.
   
   The FDA has recently approved an immunochromatographic membrane assay to detect S. pneumoniae antigen in urine. Results may be obtained as quickly as 15 min after initiation of the test. According to the package insert, the test has a sensitivity of 86% and a specificity of 94%. Disadvantages are the limited experience with the assay, the need for cultures in order to determine susceptibility to guide therapy, and the lack of published data on performance characteristics. The IDSA panel endorses this test as a complement to sputum and blood cultures (C-III).
   
   The Quellung test also is a rapid assay to detect S. pneumoniae but requires adequate expertise. Rapid, commercially available EIAs are available for detection of respiratory syncytial virus (RSV), adenovirus, and parainfluenza viruses 1, 2, and 3. The sensitivities of these tests are >80%. Rapid methods to detect influenza virus are of special interest because of the availability of antiviral agents that must be given within 48 h of the onset of symptoms. These tests show sensitivities of 70% 85% and a specificity >90%. Clinical detection of influenza on the basis of typical symptoms during an influenza epidemic appears more sensitive [100].
   The urinary antigen tests have been shown to be sensitive and specific for detection of L. pneumophila serogroup 1, which accounts for 70% of reported legionella cases in the United States [46, 98]; other possible advantages are the technical ease with which the test is performed and the validity of results after several days of effective antibiotic treatment. DFA staining of respiratory secretions is technically demanding, shows optimal results with L. pneumophila, and shows poor sensitivity and specificity when not performed by experts using only certain antibodies. Culture and urine antigen testing show sensitivity of 50% 60% and a specificity of >95%. A negative laboratory test does not exclude Legionella, particularly if the case is caused by organisms other than L. pneumophila serogroup 1, but a positive culture or urine antigen assay is virtually diagnostic. The IDSA panel recommends urinary antigen assays and sputum culture on selective and nonselective media, with specimen decontamination before plating, to detect legionnaires' disease (A-II).
   
6. DNA probes and amplification: several rapid diagnostic tests that use nucleic acid amplification for the evaluation of respiratory secretions or serum are presently under development, especially for Chlamydia, Mycoplasma, and Legionella [66]. The reagents for these tests have not been cleared by the FDA, and their availability is generally restricted to research and reference laboratories [66, 96]. If such tests become available, they may be helpful in establishing early diagnosis and allowing for directed therapy at the time of care. Their greatest potential utility is anticipated for the detection of M. pneumoniae, Legionella, and selected pathogens that infrequently colonize the upper airways in the absence of disease (table 9).
7. Invasive diagnostic tests (transtracheal aspiration, bronchoscopy, and percutaneous lung aspiration; table 3): transtracheal aspiration was previously used to obtain uncontaminated lower respiratory secretions that were valid for culture for the detection of anaerobic organisms, as well as common aerobic pathogens [62, 89]. This procedure is now infrequently performed because of concern about adverse effects and the lack of personnel skilled in the technique. A consequence of reduced use of transtracheal aspiration is the lack of any method to detect anaerobic bacteria in the lung in the absence of empyema or bacteremia.
   
   The utility of fiber-optic bronchoscopy is variable, depending on pathogen and technique. Because aspirates from the inner channel of the bronchoscope are subject to contamination by the upper airway flora, they should not be cultured anaerobically, since they have the same limitations as expectorated sputum [89, 101]. For recovery of common bacterial pathogens, quantitative culture of BAL or of a protected-brush catheter specimen is considered superior [102, 103]. The techniques for collection, transport, and processing of specimens for quantitative culture are available from published sources [89, 102, 103]. Bronchoscopy is impractical for routine use, because it is expensive, requires technical expertise, and may be difficult to perform in a timely manner. Some authorities favor its use in patients with a fulminant course, who require admission to an ICU, or have complex pneumonia unresponsive to antimicrobial therapy [89, 93, 104, 105]. Bronchoscopy is especially useful for the detection of selected pathogens, such as P. carinii, Mycobacterium species, and cytomegalovirus [89].
   

Most important, resistance extends far beyond the ß-lactam antibiotics. Although the genetics of pneumococcal resistance is complex,ß -lactam resistant organisms often have acquired genes that confer resistance to other classes of antimicrobials through transformation or conjugative transposons. Thus, pneumococci that are penicillin-resistant are also often resistant to other antibiotics, and the most appropriate term to characterize them is multiply antibiotic-resistant (table 11; these data reflect the general situation in the United States as of October 1999). Resistance to some of these antimicrobials can be overcome by increasing the dose of antibiotic.

Macrolides are an example. In the United States, most macrolide resistance is a result of increased drug efflux encoded by mefE (erythromycin MIC, 2 32 µg/mL, and susceptible to clindamycin); it is possible that this resistance may be overcome by achievable levels of macrolides [114]. In Europe, most macrolide resistance is due to a ribosomal methylase encoded by ermAM; this results in high-grade resistance to macrolides and resistance to clindamycin that probably cannot be overcome. It is important to emphasize that resistance to newer macrolides, such as azithromycin or clarithromycin, parallels resistance to erythromycin. The prevalence of resistance to tetracyclines among pneumococci is similar to that of resistance to macrolides, but resistance to trimethoprim-sulfamethoxazole (TMP-SMZ) is far more prevalent, and use of this combination is discouraged [109 112]. Among FDA-approved drugs, only vancomycin and linezolid are currently effective against essentially all pneumococci. Fluoroquinolones are active against >98% of strains, including penicillin-resistant strains, but resistance to these drugs has begun to increase in some areas where they are used extensively [115 118]. Of the newer drugs, the oxazolidinones [119] and glycopeptides [120] appear to be most promising, with MICs for drug-resistant S. pneumoniae being no higher than those for penicillin-susceptible strains. Resistance to the streptogramins appears to parallel that to the macrolides.

Studies of oral outpatient therapy for pneumonia, in which the majority of cases have probably been due to S. pneumoniae, have shown a good outcome, regardless what therapy is given; however, these studies were not designed to examine antibiotic resistance among pneumococci. Recommended antimicrobial agents for empirical treatment of pneumococcal pneumonia include amoxicillin (500 mg thrice daily), cefuroxime axetil (500 mg twice daily), cefpodoxime (200 mg twice daily), cefprozil (500 mg twice daily), and azithromycin, clarithromycin, erythromycin, or a quinolone or doxycycline in ordinarily prescribed dosages. Amoxicillin is preferred to penicillin because of more reliable absorption, longer half-life, and slightly more favorable MICs. Although recent surveillance studies indicate increasing resistance to macrolides, to date there is a paucity of reports of clinical failure in patients without risk factors for infection with drug-resistant S. pneumoniae [114]. With increasing use, however, there is concern about reduced efficacy of macrolides.

In hospitalized patients, pneumococcal pneumonia caused by organisms that are susceptible or intermediately resistant to penicillin responds to treatment with penicillin (2 million units every 4 h), ampicillin (1 g every 6 h), cefotaxime (1 g every 8 h), or ceftriaxone (1 g every 24 h). Pneumonia due to penicillin- or cephalosporin-resistant organisms probably requires higher doses of these drugs. Retrospective studies [121, 122] have shown a similar outcome after treatment with standard doses of a penicillin or a cephalosporin, without regard to whether pneumonia was due to susceptible or nonsusceptible organisms, but the number of subjects infected with resistant pneumococci (MIC, 2 g/mL) was very small, and there was a trend toward worse outcomes in both studies [121, 122].
A CDC study found mortality associated with treated pneumococcal pneumonia to be increased 3-fold when the condition was due to penicillin-resistant pneumococci and 7-fold when due to ceftriaxone-resistant pneumococci, even after adjusting for severity of underlying illness and previous hospitalization, both of which increase the likelihood that resistant pneumococci will be present [123]. This study, however, did not determine the nature of the treatment in each case. It seems likely that, ultimately, penicillin or ceftriaxone may not reliably cure infection caused by strains of S. pneumoniae for which penicillin MICs are 4 g/mL and ceftriaxone MICs are 8 g/mL.

At present, many authorities treat pneumococcal pneumonia, even in critically ill patients, with cefotaxime (1 g every 6 8 h) or ceftriaxone (1 g every 12 24 h). Many patients have received 1 2 g of ampicillin (with or without sulbactam) every 6 h, with a good response. Although vancomycin is nearly certain to provide antibiotic coverage, there is a strong impetus not to use this drug until it is proven to be needed because of fear of the emergence of resistant organisms. Vancomycin or a fluoroquinolone should be used for initial treatment of pneumococcal pneumonia in critically ill patients who are allergic to -lactam antibiotics. Quinupristin/dalfopristin or linezolid are other options, but experience with these antimicrobial agents for pneumococcal pneumonia is extremely limited.

Management recommendations within this document are restricted to immunocompetent adults with acute CAP and are stratified on the basis of whether patients are treated as outpatients or are hospitalized (figure 2). Emphasis is accorded to the following:

1. 1. Rational use of the microbiology laboratory: patients who are candidates for hospitalization with acute pneumonia should have blood cultures performed and an expectorated sputum specimen collected (in the presence of the physician whenever possible) before antimicrobial administration, unless these procedures would substantially delay initiation of treatment (B-II). Consensus is lacking as to the need for microbiological diagnosis for outpatients, although preparation of an air-dried, heat-fixed slide of sputum (obtained before antimicrobial treatment for subsequent Gram staining) is desirable. Investigation for selected microbial pathogens, such as Legionella and Mycobacterium, will depend on clinical features.

1. Pathogen-directed antimicrobial therapy: an attempt should be made to achieve pathogen-directed antimicrobial therapy for hospitalized patients (C-III; table 14). This decision should be made when relevant information becomes available, and its strength is greatest in cases when an established etiologic agent has been identified, according to criteria described above. Empirical selection of antimicrobial agents, when necessary, should be directed against the pathogens that are most common and treatable, according to the setting (table 15). Antibiotic regimens selected empirically should be changed when results of culture and in vitro sensitivity tests become available, on the assumption that clinical and microbiological correlations support this tactic

1. Table Pathogen-directed antimicrobial therapy for community-acquired pneumonia

1. Prompt antimicrobial treatment: antimicrobial treatment should be initiated promptly after the diagnosis of pneumonia is established with radiography and after Gram stain results are available to facilitate antimicrobial selection. For patients requiring hospitalization for acute pneumonia, it is important to initiate therapy in a timely fashion; an analysis of 14,000 patients showed that a >8-h delay from the time of admission to initiation of antibiotic therapy was associated with an increase in mortality (B-II) [188]. Antibiotic treatment should not be withheld from acutely ill patients because of delays in obtaining appropriate specimens or the results of Gram stains and cultures.
2. 5. Decisions regarding hospitalization based on prognostic criteria, as summarized in table 4 (A-I): in addition, this decision will be influenced by other factors, such as the availability of home support, probability of compliance, and availability of alternative settings for supervised care. Many patients with CAP are hospitalized for a concurrent disease process. Studies show that 25% 50% of admissions for CAP are for these other considerations, which extend beyond those listed as admission criteria in table 4 [10, 36].

1. Incorrect diagnosis (not an infection or underlying noninfectious disease with infectious component): noninfectious illnesses that may account for the clinical and radiographic findings include congestive heart failure, pulmonary embolus, atelectasis, sarcoidosis, neoplasms, radiation pneumonitis, pulmonary drug reactions, vasculitis, ARDS, pulmonary hemorrhage, and inflammatory lung disease.

1. Correct diagnosis: if a correct diagnosis has been made, but the patient fails to respond, the physician should consider each of the following components of the host-drug-pathogen triad.
   (a)Host-related problem: the overall reported mortality for hospitalized patients with CAP is 10% 15%; this figure includes patients with an established or likely etiologic diagnosis who are treated with appropriate antibiotics [9]. The mortality rate for patients with bacteremic pneumococcal pneumonia caused by penicillin-susceptible strains of S. pneumoniae and treated with penicillin has been consistently reported at 20% [121]. The usual explanation is that physiological events, often in the form of cascades, have been set in motion and are not reversed by simply killing the infecting organism. Occasional patients have local lesions that preclude optimal response, such as obstruction by a neoplasm or a foreign body. Empyema is an infrequent but important cause of failure to respond. Other complications include adverse drug reactions, other complications of medical management such as fluid overload, pulmonary superinfection or sepsis from an iv line, or any of a host of medical complications related to hospitalization.
   (b)Drug-related problem: whether a specific pathogen has been isolated, if a correct etiologic diagnosis of pneumonia has been made, but the patient does not appear to be responding, the physician should always consider the possibility of a medication error, an inappropriate dosing regimen, a problem with compliance, malabsorption, a drug-drug interaction that reduces antimicrobial levels, or other factors that may alter drug delivery to the site of infection. Drug fever or another adverse drug reaction may obscure response to successful therapy.
   (c)Pathogen-related problem: the causative organism may have been identified correctly but may be resistant to the antibiotic administered. Examples might include a penicillin-resistant pneumococcus, methicillin-resistant S. aureus, or a multiresistant gram-negative-bacillus rod. The wide variety of other pathogens that might not be identified and would not be expected to respond to some or all of the regimens recommended for empirical use include M. tuberculosis, fungi, viruses, Nocardia, C. psittaci, hantavirus, C. burnetii, or P. carinii. In some cases, these or other organisms may represent copathogens.
2. Assessment of a nonresponding patient: the assessment of a patient who fails to respond to initial empirical therapy should take into account the possibilities outlined above and in figure 3. Tests appropriate to the individual disease entities should be used to exclude noninfectious possibilities. Specific examples include ventilation-perfusion lung scans and, in selected cases, pulmonary angiography to identify pulmonary embolus, identification of antineutrophil cytoplasmic antibody, and bronchoscopy or open-lung biopsy to diagnose a variety of noninfectious causes. Some host factors that might influence the range of pathogens, as well as the response, include HIV infection, cystic fibrosis, neoplasms, recent travel, and unusual exposures.
   For those cases in which infection is responsible for the clinical and radiographic findings, issues relating to the host-drug-pathogen triad should be taken into account during the work up. To rule out an endobronchial lesion or foreign body, bronchoscopy and/or CT scanning may be of help. To ensure that a sequestered focus of infection, such as a lung abscess or empyema, has not developed, thereby preventing access of the drugs to the pathogens, CT scanning of the chest may be useful. For pleural effusions detected on chest radiograph, ultrasonography can localize the collection and provide an estimate of the volume of fluid.
   Infection caused by an unsuspected organism or a resistant pathogen must always be a concern with regard to the nonresponding patient. An aggressive attempt to obtain appropriate expectorated sputum samples may lead to identification of such organisms on stain or culture, although the validity of such posttreatment specimens must be questioned because of the inability to culture S. pneumoniae and other fastidious pathogens and frequent overgrowth by S. aureus and gram-negative bacilli. In selected cases, bronchoscopy may be necessary; 1 study suggested that helpful information may be provided by this procedure for up to 41% of patients with CAP whose initial empirical antimicrobial therapy fails [73].