Riassunto
Le presenti linee guida per la definizione della fase preanalitica dell’esame delle urine sono state predisposte sotto gli auspici della Società Italiana di Medicina di Laboratorio (SIMeL) e della Società Italiana di Biochimica Clinica e Biologia Molecolare Clinica (SIBioC). L’analisi delle urine, comprendente la valutazione microbiologica e l’esame chimico-fisico e morfologico, dovrebbe sempre essere eseguita sulla base di un appropriato quesito diagnostico e dovrebbe essere possibile selezionare il livello analitico idoneo da erogare in base al suddetto quesito, in base alla tipologia del paziente e della tecnologia disponibile. La documentazione di riferimento per l’esecuzione dell’esame delle urine dovrebbe comprendere un’accurata descrizione delle fasi preanalitica, analitica e post-analitica. Una corretta documentazione per la fase preanalitica dovrebbe prevedere istruzioni adeguate in merito alla preparazione del paziente, alla raccolta, alla conservazione e al trasporto del campione. Sarebbe inoltre auspicabile che ciascun Laboratorio dichiarasse esplicitamente le proprie competenze specifiche e quindi il livello delle prestazioni erogabili. L’esame chimico e morfologico delle urine ha subito una considerevole trasformazione negli ultimi anni ed è giunto il momento di aggiornare e modificare le fasi del processo analitico. Le nuove tecnologie, che hanno reso i risultati della morfologia urinaria assai più rilevanti in termini di precisione e accuratezza, hanno anche evidenziato la necessità di perfezionare e di assicurare la qualità nella fase preanalitica. Sono state inoltre considerate sia le opportunità di consolidamento e standardizzazione della fase analitica, sia la ridefinizione degli obiettivi clinici e del referto, per renderlo completo, integrato e il più significativo possibile per il clinico. Queste linee guida sono state elaborate sulla base dei dati di letteratura e delle esperienze personali degli autori. Gli aspetti più rilevanti appaiono essere i seguenti:
-
l’analisi delle urine dovrebbe essere eseguita sulla base di una specifica richiesta clinica
-
il campione raccomandato è il mitto intermedio della prima minzione del mattino, ottenuto dopo pulizia dei genitali
-
ogni Servizio di Medicina di Laboratorio dovrebbe preparare istruzioni scritte (con illustrazioni, se possibile) concernenti le procedure di raccolta del campione
-
è raccomandato l’uso di un contenitore standard per la raccolta del campione
-
è raccomandato l’utilizzo di un adeguato sistema di etichettatura dei campioni
-
l’analisi delle urine dovrebbe essere eseguita prima possibile
-
qualora si prevedano dei ritardi nell’esecuzione dell’esame superiori alle 4 ore dalla raccolta, è necessario refrigerare (+4–8 °C) i campioni
-
è necessaria la predisposizione di procedure adeguate per il trasporto, il trattamento e la conservazione dei campioni
-
è necessaria la trasmissione di informazioni accurate relative alla fase preanalitica tra i punti di raccolta e il Laboratorio che esegue l’analisi; le eventuali violazioni della procedura standard devono essere sempre registrate
-
ogni Laboratorio dovrebbe dichiarare il livello analitico (ad es. la tipologia dei test) che è in grado di erogare.
Auspichiamo che queste linee guida, relative alla fase preanalitica dell’esame delle urine, possano essere implementate nell’ambito delle procedure di ogni Laboratorio, migliorando la qualità del processo e del prodotto, contribuendo a far sì che la fase analitica rifletta la reale situazione dell’apparato urinario dell’utente/paziente.
Summary
These guidelines for the definition of the preanalytical phase of urinalysis were drafted under the auspices of the Italian Society of Laboratory Medicine (SIMeL) and the Italian Society of Clinical Biochemistry and Clinic Molecular Biology (SIBioC). Urinalysis, including both morphological assay and microbiological examination, should always be performed on the basis of an appropriate medical request, and the relative analyses should be selected according to the clinical needs, the patient and the available technology. The reference materials for comprehensive urine examinations should include clear and intelligible recommendations for the preexamination, examination and postexamination procedures. A correct preexamination procedure should include accurate information about the preparation of the patient, and collection, handling, preservation, storage and transport of the specimen. A description of the local skinless and therefore the hierarchical level of urinalysis is also recommended. The chemical/morphological urine examination has undergone some changes over the last few years. As such, it might be the to update and modify accordingly the various activities throughout the total testing process. The advent of new technologies, which have made the laboratory report much more significant as regards the morphological features of this test, has also promoted some reflections about the necessity for further refining and improving the quality of the preexamination process. This can be treated as an opportunity not only to consolidate and standardize the examination process, but also to redefine the clinical objectives by developing a complete, integrated and more clinically meaningful report. These guidelines were elaborated and drafted on the basis of the current literature and the personal experience of the authors. The more significant aspects of these guidelines are the following:
-
Urinalysis should be performed on the basis of a specific clinical need.
-
The sample recommended for urinalysis is the first morning urine collected using a voided midstream technique.
-
Each service of laboratory medicine should make available to the stakeholders printed instructions (with illustrations, whenever possible) concerning the appropriate procedure for collection of specimens.
-
The use of standard devices for urine collection is recommended.
-
The use of an appropriate labelling system is recommended.
-
Urinalysis should be performed as soon as possible after collection. If examination is to be delayed by more than 4 hours, then the samples should be refrigerated.
-
The preparation of adequate protocols for handling, transport and storage of the samples is mandatory.
-
It is necessary to transmit preexamination information from the collection sites to the laboratory that performs the analysis. Deviations from the standard should always be recorded.
-
The hierarchical analytical level available in each laboratory should be declared.
We hope that these guidelines concerning the preexamination process of urinalysis have a positive impact on the validation of local working practice, producing a significant improvement in the overall quality of this test (and in the whole field of laboratory medicine as well), so that the results of testing will reflect the real condition of the urinary system of the patient.
Bibliografia
Khan KS, Coomarasamy A (2004) Searching for evidence to inform clinical practice. Curr Obstet Gynaecol 14:142–146
Lilford R, Richardson A, Stevens A et al (2001) Issues in methodological research: perspectives from researchers and commissioners. Health Technol Assess 15:1–57
Grilli R (2002) AGREE — uno strumento per la valutazione della qualità delle linee guida. Dossier 60. Agenzia Sanitaria Regionale dell’Emilia-Romagna, Bologna
European Confederation of Laboratory Medicine (ECLM) (2000) European Urinalysis Guidelines. Scand J Clin Lab Invest 60:1–96
Rabinovitch A, Arzoumanian L, Curcio KM et al (2009) Urinalysis; Approved Guideline -Third Edition, GP16A3. Clinical and Laboratory Standards Institute (CLSI), Wayne, pp 4–21
Scottish Intercollegiate Guidelines Network (SIGN) (2006) Management of suspected bacterial urinary tract infection in adults. A National Clinical Guideline. SIGN publication n. 88, Edinburgh
Atkins D, Best D, Briss P et al (2004) Grading quality of evidence and strength of recommendations. BMJ 328:1490
Guyatt G, Gutterman D, Baumann MH et al (2006) Grading strength of recommendations and quality of evidence in clinical guidelines: report from American College of chest physicians task force. Chest 129:174–181
Kouri T, Gyory A, Rowan M (2003) ISLH recommended procedure for the enumeration of particles in urine. Lab Hematol 9:58–63
Aspevall O, Hallander H, Gant V et al (2001) European guidelines: a collaborative document produced by European clinical microbiologists and clinical chemists under ECLM in collaboration with ESCMID. Clin Microbiol Infect 7:173–178
British Columbia Guidelines and Advisory Committee (2004) Protocol for macroscopic and microscopic urinalysis and investigation of urinary tract infections 2002. www.health.gov.bc.ca/msp/legislation/communiques/1998vol3-2.pdf-334kb
Fogazzi G, Garigali G, Pirovano B et al (2007) How to improve the teaching in urine ulti cent. Clin Chem Lab Med 45:407–412
Kouri T, Malminiemi O, Penders J (2008) Limits of preservation of samples for urine strip tests and particle counting. Clin Chem Lab Med 46:703–713
Agenzia Sanitaria e Sociale Regionale dell’Emilia-Romagna (2010) Infezioni delle vie urinarie nell’adulto. Linea Guida Regionale. Dossier 203/2011. http://asr.regione.emilia-romagna.it/wcm/asr/collana_dossier/doss190.htm
Bertolissi A, Lanzafame P, Screm M et al. Azienda Ospedaliera Santa Maria della Misericordia. Linee Guida: La Diagnosi Microbiologica delle infezioni Urinarie. http://www.ospedaleudine.it
Gillespie T, Fewster J, Masterton R (1999) The effect of specimen processing delay on borate urine preservation. J Clin Pathol 52:95–98
Meers P, Chow C (1990) Bacteriostatic and bactericidal actions of boric acid against bacteria and fungi commonly found in urine. J Clin Pathol 43:484–487
Watson P, Duerden B (1977) Laboratory assessment of physical and ulti c methods of ulti cent urine specimens. J Clin Pathol 30:532–536
Lauer BA, Reller LB, Mirrett S (1979) Evaluation of preservative fluid for urine collected for culture. J Clin Microbiol 10:42–45
Froom P, Bieganiec B, Ehenrich Z et al (2000) Stability of common analytes in urine refrigerated for 24 h before automated analysis by test strips. Clin Chem 46:1384–1386
Eriksson I, Lindmann R, Thore M (2002) Microbiological evaluation of a commercial ulti cent system for urine samples. Scand J Clin Lab Invest 62:325–335
Kass E (1956) Asymptomatic infections of the urinary tract. Trans Assoc Am Phys 69:56–63
Kass EH (1957) Bacteriuria and the diagnosis of infections of the urinary tract; with observations on the use of methionine as a urinary antiseptic. AMA Arch Intern Med 100:709–714
Lohr J, Donowitz L, Dudley S (1986) Bacterial contamination rates for non-clean-catch and clean-catch midstream urine collections in boys. J Pediatr 109:659–660
Lohr JA, Donowitz LG, Dudley SM (1989) Bacterial contamination rates in voided urine collections in girls. J Pediatr 114:91–93
Lifshitz E, Kramer L (2000) Outpatient urine culture: does collection technique matter? Arch Intern Med 160:2537–2540
Prandoni D, Boone M, Larson E et al (1996) Assessment of urine collection technique for microbial culture. Am J Infect Control 24:219–221
Morris R, Watts M, Reeves D (1979) Perineal cleansing before midstream urine, a necessary ritual? Lancet 2:158–159
Leisure M, Dudley S, Donowitz L (1993) Does a clean-catch urine sample reduce bacterial contamination? N Engl J Med 328:289–290
Wheldon DB, Slack M (1977) Multiplication of contaminant bacteria in urine and interpretation of delayed culture. J Clin Pathol 30:615–619
Rogers J, Saunders C (2008) Urine collection in infants and children. Nurs Times 104:40–42
Koneman E, Allen S, Dowell V et al (1987) Testo Atlante di Microbiologia Diagnostica. Antonio Delfino, Roma
Fuller C, Threatte G, Henry J (2001) Basic examination of the urine. In: Henry JB, Davey FR, Herman CJ et al (ed) Clinical diagnosis and management by laboratory methods, 20th edn. WB Saunders, Philadelphia, pp 367–402
Cheng Y, Wong S (2005) Diagnosing symptomatic urinary tract infections in infants by catheter urine culture. J Paediatr Child Health 41:437–440
Gilljam B, Svensson M (2008) In-out catheterization of young children with suspected urinary tract infection: a retrospective journal study. Pediatr Nurs 34:241–245
Metchock BG, Nolte FS, Wallace RJ (1999) Mycobacterium. In: Murray PR, Baron EJ, Pfaller MA, Tenover FC, Yolken RH (eds) Manual of clinical microbiology, 7th edn. American Society for Microbiology Press, Washington DC, pp 399–437
Peter J, Green C, Hoelscher M et al (2010) Urine for the diagnosis of tuberculosis: current approaches, clinical applicability, and new developments. Curr Opin Pulm Med 16:262–270
Anosike J, Okere A, Nwoke BE et al (2003) Endemicity of vesical schistosomiasis in the Ebonyi Benue river valley, south eastern Nigeria. Int J Hyg Environ Health 206:205–210
Keuzer M, Brandts R (1997) Flow cytometer and the urine Laboratory: Field evaluation of the Sysmex UF-100. Sysmex Intern Journ 7:117–122
Ottiger C, Huber A (2003) Quantitative urine particles analysis: Integrative approach for the optimal combination of automation with UF-100 and microscopic review with KOVA cell chambre. Clin Chem 49:617–623
Lamchiagdhase P, Preechaborisutkull K, Lomsomboon P et al (2005) Urine sediment examination method and the iQ200 automated urine ulti cent analyzer. Clin Chim Acta 358:167–174
Wah D, Porntip K, Butch (2005) Analytic performance of the iQ200 automated urine microscopy analyzer and comparison with manual counts using Fuchs-Rosenthal cell cambers. Am J Clin Pathol 123:290–296
Zaman Z, Fogazzi GB, Garigali G et al (2010) Urine sediment analysis: Analytical and diagnostic performance of sediMAX — a new automated microscopy image-based urine sediment analyser. Clin Chim Acta 41:147–154
European Committee for Standardization (1996) In vitro diagnostic system: tansport packages for medical and biological specimens. Requirements tests. CEN, Brussels.
Manoni F, Valverde S, Caleffi A et al (2008) Stability of common analytes and urine particles stored at room temperature before automated analysis. Riv It Med Lab 4:192–198
Manoni F, Valverde S, Caleffi A et al (2010) Esame delle urine: è tempo di cambiare. Riv It Med Lab 6:52–58
Tencer J, Thysell H, Andersson K et al (1994) Stability of albumin, protein HC, immunoglobulin G, Kappa and Lambda chain immunoreactivity, orosomucoid and alpha 1 antitrypsin in urine stored at various condition. Scand J Clin Lab Invest 54:199–206
Kierkegaard H, Feldt-Rasmussen U, Hoerder M et al (1980) Falsely negative urinary leukocyte counts due to delayed examination examination. Scand J Clin Lab Invest 40:259–261
Ampalahan M, Birch D, Becker G (1994) Chimica preservation of urine sediment for phase contrast ulti cent examination. Nephron 68:180–183
Porter J, Brodie J (1969) Boric acid preservation of urine samples. Br Med J; 2: 353–355
Grosso S, Bruschetta G, De Rosa R (2008) Improving the efficiency of pre analytical and analytical work flow of urine cultures with flow cytometry. New Microb 31:501–505
Roggeman S, Zaman Z (2001) Safely reducing manual urine microscopy analyses by combining urine flow cytometer and strip results. Am J Clin Pathol 116:872–878
Miller JM (1996) A guide to specimen management in clinical microbiology. American Society for Microbiology, Washington DC
Addis T (1926) The number of formed elements in the urinary sediment of normal individuals. J Clin Invest 2:409–415
Gadeholt H (1964) Quantitative estimation of urinary sediment with special regard to source of errors. Br Med J 1:1547–1549
Fairley K, Birch D (1993) Microscopic urinalysis in glomerulonephritis. Kidney Int 44:S9–S12
Shayanfar N, Tobler U, von Eckardstein A et al (2007) Automated urinalysis: first experiences and a comparison between the Iris iQ200 urine microscopy system, the Sysmex UF-100 flow cytometer and manual microscopic particle counting. Clin Chem Lab Med 45:1251–1256. Erratum in: Clin Chem Lab Med 2007; 45:1570
Regeniter A, Haenni V, Risch L et al (2001) Urine analysis performed by flow cytometry: reference range determination and comparison to morphological findings, dipstick chemistry and bacterial culture results — a multicenter study. Clin Nephrol 55:384–392
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Manoni, F., Caleffi, A., Gessoni, G. et al. L’esame delle urine chimico morfologico e colturale: proposta di linee guida per una procedura standardizzata della fase preanalitica. Riv Ital Med Lab 7, 25–35 (2011). https://doi.org/10.1007/s13631-011-0005-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13631-011-0005-0