M. Ammirabile, C. Ferraris Fusarini, A.C. Migliorini, E. Locatelli, R. Maiavacca, F. Ceriotti
UOC Lab analisi, Fondazione IRCCS Ca' Granda Osp. Maggiore Policlinico, Milano
La pertosse è una malattia respiratoria acuta, causata dal batterio gram-negativo Bordetella pertussis. Si registrano 30 milioni di casi/anno; i bambini con meno di 5 anni muoiono nello 0.53% dei casi(1). I sintomi sono simili a quelli di un raffreddore; seguono poi violenti attacchi di tosse. La diagnosi avviene con real time PCR. Il trattamento antibiotico elettivo è costituito da azitromicina/ claritromicina(2). La prevenzione avviene soprattutto con il vaccino, somministrato a partire dall’ottava settimana di vita.
Nel febbraio 2018 arriva, presso il laboratorio di ematologia, l’emocromo di un bambino di sei settimane, proveniente dal pronto soccorso pediatrico. Si registra un aumento dei globuli bianchi (41.31 109/L [5.0-16.6]), di cui il 60% è costituito da linfociti, e delle piastrine (704 109/L [130-400]). Al microscopio ottico, dopo colorazione con May-Grunwald Giemsa, i linfociti appaiono di piccole- medie dimensioni e con rapporto nucleo/citoplasma >1. La maggior parte ha un nucleo clivato, con una profonda incisura; altri hanno un nucleo convoluto. La morfologia, unita ai dati dell’emocromo, fa pensare a una proliferazione linfocitaria causata da un’infezione. Consultando la cartella clinica si scopre che al bimbo, portato in ospedale per insufficienza respiratoria e cianosi periorale, è stato effettuato anche un aspirato nasofaringeo per cercare, mediante real time PCR, DNA/ RNA batterici e virali. L’esame rivela la presenza di B.pertussis. Il paziente riceve supporto respiratorio, è trattato con azitromicina ed è somministrata un’infusione glucosalina. Dopo alcuni giorni si assiste a una buona ripresa clinica.
Il caso sottolinea l’importanza di un’attenta e precisa osservazione microscopica. In presenza di linfocitosi periferica, unita al riscontro di linfociti clivati, e di dati clinici opportuni, è possibile pensare a un caso di pertosse. Il laboratorio quindi, descrivendo la morfologia linfocitaria, può aiutare il clinico in una diagnosi rapida, portandolo a definire una corretta e tempestiva terapia antibiotica, ancora prima che siano disponibili i risultati molecolari. 1) del Valle-Mendoza J et al. BMC Res Notes 2018; 11, 318
2) Altunaiji MS et al. Cochrane Database of Systematic Reviews 2007, DOI: 10.1002/14651858.
P052
A CASE OF IgD LAMBDA MULTIPLE MYELOMA AND ACUTE RENAL FAILURE WITHOUT M-SPIKE IN SERUM ELECTROPHORESIS
T. Troiano1, L. Demarinis1, S. De Francesco1, A. Lamanna1, F. Di Serio1, V. Montinaro2
1
U.O. Patologia Clinica Ospedaliera, Azienda Ospedaliera Universitaria Policlinico di Bari
2Sez. Nefrologia, Dialisi e Trapianto di Rene, Dip.
Emergenza e Trapianti d'Organo, Università degli Studi di Bari
Background: IgD multiple myeloma (MM) is a rare subtype of this disorder, accounts for less than 2% of all myeloma. It usually affects a younger population and is characterized by their poor prognosis than other MM isotypes. The distinctive features are the predominant occurrence in males, predominance of λ light chains, frequent renal impairment and uncertain appearance of M-component in serum electrophoresis. A quick correct laboratory diagnosis means establishing appropriate treatment early and a better prognosis for patients. Methods: A 57 years old man with history blood hypertension was admitted to Renal Unit in August 2016 because hyperpyrexia, left-lower limb pain, weight loss and acute renal failure. In October the patient was admitted again to Renal Unit for flare-up of symptoms. The laboratory diagnostic workup was oriented both to the evaluation of renal failure and to the research of the monoclonal component, with serum protein electrophoresis (CZE), serum Immunofixation (s- IFE), urine Immunofixation (u-IFE) (Sebia) and sFLC (The Binding Site). Results: Laboratory investigation showed eGFR 20 mL/min, haemoglobin 9,4 gr/dl; the CZE showed absent M-spike; s-IFE, with standard antisera, showed one monoclonal band λ without corresponding heavy-chain band, a second s-IFE using antisera to IgD and IgE showed a monoclonal IgD no corresponding
λ band. The immunoselection technique was used to establish the presence of IgD λ and λ free band. The FLCλ 2348 mg/L, FLCk 92,3 mg/L, ratio k/λ 0,04.; u- IFE yielded a Bence Jones proteinuria λ. Bone marrow biopsy showed plasmacellular infiltration > 20%; kidney biopsy confirmed diagnosis “light chain cast nephropathy”. Conclusions: The present case demonstrates that IgD MM may be associated with an extensive production of FLC which may be responsible for renal failure and may thus misdiagnosed as a LCMM. Knowledge of its typical laboratory feature is crucial to establish the correct diagnosis. It is important to perform s-IFE using antisera to IgD in case monoclonal light chain bands without corresponding heavy-chain bands at the first diagnosis. Bibliografia: Robier C. et al: IgDλ myeloma with extensive free light-chain excretion: a diagnostic pitfall in the identification of monoclonal gammopathies. Clin Chem Lab Med 2017; 55(7):137-139.
P053
AN UNUSUAL IgE/LAMBDA-SECRETING MULTIPLE MYELOMA
M.P. Campisi1, A.M. Scotta 1, D. Duranti1, R. Serino1, M.G. Sulas1, M. Vidali1, M. Bagnati1, G. Bellomo1, L. De Paoli2, U. Dianzani1, I. Crespi1
1Clinical Chemistry Laboratory, Department of Health
Sciences, Università del Piemonte Orientale, AOU Maggiore della Carità, Novara, Italy
2
Institute of Hematology, Department of Translational Medicine, Università del Piemonte Orientale, AOU Maggiore della Carità, Novara, Italy
Background: IgE-secreting multiple myeloma is a rare disease characterized by a high frequency of Bence- Jones proteinuria and plasma cell leukaemia when compared to other isotypes of monoclonal proteins. Less than 50 cases have been reported in literature, but the real number could be higher since monoclonal anti-D and anti-E antibodies are not usually employed in the immunofixation, when an exclusive band related to the free light chains lambda or kappa is present.
Patient and Methods: a 79-year-old man was hospitalized for urosepsis. Radiological images showed a spread osteolysis and an important femoral metaphysic osteolysis that caused the detachment of the small trochanter. Other biochemical findings evidenced a mild microcytic anemia (Hb 9.10 g/dL, MCV 67.2), a normal renal function and no hypercalcemia. Serum was tested for capillarys electrophoresis (CZE SEBIA) and immunofixation (IF) (Hydragel IF 2/4 and Hydragel 2IF/BJ HR, SEBIA).
Results: serum electrophoresis showed a monoclonal component (10 %) in the gamma zone that needed to be confirmed by IF in serum and urine. Serum IF was initially performed with most frequently employed antisera (IgG, IgA, IgM, kappa and lambda). In the agarose gel, a clear band was detected with the lambda light chain not corresponding to any band detected with heavy chain antisera. So it was necessary to procede with a subsequent immunofixation including other antisera (IgD, IgE, lambda and free lambda) in order to have a more complete typing of the monoclonal component. The final characterization was consistent with a monoclonal gammopathy IgE/lambda. Urine IF revealed a Bence Jones positive for lambda free.
Immunohistochemistry of bone-marrow biopsy confirmed the occurrence of Multiple Myeloma IgE/lambda (lambda monoclonal infiltrate 60%).
Conclusion: the diagnosis of rare multiple myelomas, like IgE/lambda gammopathy, needs a particular and deep approach. The presence of a monoclonal band in the light chain lane, without correspondence in the most common heavy chains (IgG, IgA and IgM) lanes, needs to be investigated for the less common IgD and IgE chains. This more accurate diagnostic investigation allows to obtain a correct diagnosis excluding a misdiagnosis of a microsecretory myeloma.
P054
L’IMPORTANZA DELLO SCREENING DEI DIFETTI