Bronchiolite Bronchiolite L’incidenza annuale è di 11.4% nei bambini sotto 1 anno e 6% tra 1-2 anni. La malattia è responsabile di 4500 decessi e 90,000 ricoveri ogni anno negli USA. Tra i bambini di 2 anni circa il 95% ha evidenza sierologica di una pregressa infezione con il virus respiratorio sinciziale. Rara nel neonato (< 28 gg) x Ab. materni Fattori di rischio: Età < 6 mesi Bambini con cardiopatia congenita Bambini con displasia broncopolmonare Bronchiolite La B. è una infiammazione acuta delle piccole vie respiratorie che esita in broncocostrizione per: mediatori della flogosi (leucotrieni) aumentata secrezione di muco distruzione delle cellule epiteliali edema delle vie aeree È una malattia tipicamente del lattante (primi 12 mesi di vita) e tipicamente di origine virale: Virus respiratorio sinciziale Virus parainfluenzale Virus influenzale Adenovirus Metapneumovirus C. trachomatis (< 4 mesi) Bronchiolitis Contagiosity The disease is highly contagious. Viral shedding in nasal secretions continues for 6 to as long as 21 days after the development of symptoms. Incubation period is from 2-5 days. Secondary infections occur in 46% of family members, 98% of other children in day care, 42% of hospital staff and 45% of previously uninfected hospitalized infants. Infection is spread by fomites via environmental surfaces. Hand washing and the use of disposable gloves and gowns may reduce nosocomial spread. Decorso (5-7 giorni) E’ una patologia tipica dei mesi invernali. Tipicamente inizia come un banale raffreddore con o senza febbre di solito di live entità e tosse. Gradualmente progredisce verso una dispnea espiratoria con: Tachipnea + tachicardia Alitamento pinne nasali Rientramenti soprasternali, intercostali e all’epigastrio Difficoltà all’alimentazione Complicanze: Disidratazione Apnee (bambini < 6 settimane) Insufficienza respiratoria Diagnosi Dispnea Wheezing (fischi e sibili su tutto l’ambito polmonare + prolungamento della fase espiratoria) Rantoli fini crepitanti diffusi Therapy The mainstays of therapy for patients with bronchiolitis are: oxygen supplementation and fluid replacement. Hypoxemia is the most common laboratory abnormality detected, and supplemental oxygen administration is common. These infants are mildly dehydrated because of decreased fluid intake and increased fluid losses from fever and tachypnea. The goal of fluid therapy is to replace deficits and provide maintenance requirements. Excessive fluid requirements should be avoided as this may promote interstitial edema formation. Corticosteroids Bronchodilators (?) Indications for pediatric intensive care referral desaturation (Sat.O2 < 90-92%) in 40% O2 (3- 4 l/min O2) PaCO2 > 60-65 mmHg pH < 7.25 cyanosis apnea acidosis Caso clinico A 16-month-old girl is evaluated in the ED for increased work of breathing. She had been seen 4 days ago for rhinorrhea, cough, vomiting, diarrhea, and fever, all of which appeared to have resolved. At that time, she had a normal CBC and serum electrolyte measurement and was treated with intravenous fluids and discharged. Two days later, she again developed cough with posttussive vomiting and rhinorrhea, but no fever or diarrhea. Caso clinico On physical examination, the girl is awake and alert but in mild-to-moderate respiratory distress. Her respiratory rate is 50 breaths/min, pulse oximetry saturation is 94%, and heart rate is 161 beats/min. She is afebrile. She has moderate pharyngeal erythema, clear rhinorrhea, and a hyperemic right tympanic membrane. Intercostal retractions, mild wheezing, and occasional scattered crackles are present. The rest of her physical findings are normal. She is given three treatments of albuterol and prednisolone and responds with a lower respiratory rate of 40 breaths/min but a pulse oximetry saturation of 92% in room air. Caso clinico She is given three treatments of albuterol and prednisolone and responds with a lower respiratory rate of 40 breaths/min but a pulse oximetry saturation of 92% in room air. Caso clinico Initial laboratory studies include negative results for respiratory syncytial virus (RSV) and influenza A and B antigens. A chest radiograph shows no acute disease and mild hyperinflation. She is admitted to the hospital. Over the next 3 days, she develops a temperature to 101°F (38.4°C) and has no improvement, despite frequent albuterol treatments. On day 4, her WBC is 9x103/mcL (9x109/L), with 41% neutrophils, 2% bands, 43% lymphocytes, and 7% monocytes, and her platelet count is 775x103/mcL (775x109/L). A urine culture is negative, but a blood culture is reported positive for gram-negative diplococci. Bronchiolite? The patient's age of 16 months in conjunction with cough, rhinorrhea, wheezing, and chest wall retractions were consistent with a diagnosis of bronchiolitis. Bronchiolitis is predominantly a viral illness (RSV, parainfluenza 3 virus, adenovirus, influenza virus) but also can be caused by Mycoplasma. Notwithstanding negative antigen tests for RSV and influenza A and B, she was treated for presumptive viral lower respiratory tract disease. The blood culture grew Moraxella catarrhalis, and she was treated for 7 days with parenteral ceftriaxone followed by 7 days of oral cefuroxime axetil. She was discharged without complications. Qualcosa di diverso? Typically, bronchiolitis reaches its most critical stage during the first 48 to 72 hours after the onset of cough. This patient's course was atypical because she developed her initial fever after 3 days of cough and wheezing, which proved to be indicative of a bacterial infection. Although uncommon, bronchiolitis may be complicated by bacterial infection (about 2% to 10% of cases). Bacterial otitis media and pulmonary bacterial coinfection, as well as associated urinary tract infection, are examples from recent literature. Sepsi? In general, a clinician should suspect sepsis whenever a patient has fever associated with behavioral changes such as irritability, fussiness, lethargy, poor feeding, and altered mental status. Tachycardia and tachypnea also may reflect sepsis. Petechiae and purpura are well-known cutaneous indicators of possible sepsis, especially meningococcemia. A weak cry and jaundice may indicate sepsis in neonates. The presentation of sepsis depends on the competency of the patient's immune system. Subtle presentations can occur in young infants and immunocompromised children, with the clinical picture influenced by the patient's level of immunity. Moraxella catarrhalis M catarrhalis is an aerobic, gram-negative diplococcus in the family Neisseriaceae that commonly inhabits the upper respiratory tract (nasopharynx), with increased seasonal colonization in fall and winter. M catarrhalis can cause acute, localized infection such as otitis media, sinusitis, conjunctivitis, and pneumonia in children. Although it causes a large proportion of cases of lower respiratory tract infection in elderly patients who have chronic obstructive pulmonary disease and chronic bronchitis, this association has not been seen in pediatric patients. Moraxella catarrhalis M catarrhalis generally is not thought of as causing invasive, systemic disease (such as meningitis and endocarditis) except in immunocompromised conditions. Risk factors for bacteremia include viral infection, sickle cell disease, malignancy, acquired immunodeficiency syndrome, and other immunodeficient states. This child did not have any other evidence of immunodeficiency; thus, additional evaluation for that state was not undertaken. It is possible that her hyperemic tympanic membrane was caused by an M catarrhalis infection, but the finding also could result from underlying viral infection. Moraxella catarrhalis This child did not have any other evidence of immunodeficiency; thus, additional evaluation for that state was not undertaken. It is possible that her hyperemic tympanic membrane was caused by an M catarrhalis infection, but the finding also could result from underlying viral infection. Moraxella catarrhalis In the clinical laboratory, isolates of M catarrhalis must be differentiated from Neisseria sp. The management and infection control differences between Neisseria sp and M catarrhalis are important. As in this case, identification of gramnegative diplococci in a patient's blood culture warrants droplet precautions for suspected meningococcemia for 24 hours while the patient receives appropriate antimicrobial therapy. Confirmation of N meningitidis also warrants antimicrobial prophylaxis for appropriate contacts. Moraxella catarrhalis Also, major management and social implications are associated with the differentiation between N gonorrhoeae and M catarrhalis when gram-negative diplococci are identified in the smear of an eye discharge from a baby who has neonatal conjunctivitis. Gonococcal neonatal conjunctivitis requires systemic antimicrobial therapy for the baby as well as evaluation and management of the mother and her partner. A final diagnosis of M catarrhalis does not raise any of these issues. Terapia More than 85% of M catarrhalis isolates are ampicillin-resistant because of betalactamase production. First-line antibiotics for focal infections (otitis media, sinusitis, pneumonia) are oral amoxicillin-clavulanate or oral second- and third-generation cephalosporins. Other antibiotics active against this organism include macrolides, trimethoprim-sulfamethoxazole, and fluoroquinolones. Terapia Sepsis generally is treated parenterally until the patient becomes asymptomatic and has a negative repeat blood culture, when treatment may be changed to oral therapy to complete a 7- to 14-day course, depending on the organism. When receiving an initial report of "gram-negative diplococci" growing in a blood culture, it is prudent to administer parenteral third-generation cephalosporins (to cover Neisseria sp and M catarrhalis) until the isolate is identified. Then, therapy can be individualized, depending on the clinical course and antimicrobial susceptibility results Messaggio da portare a casa When the course of a patient's illness does not follow the usual expectations, it is appropriate to consider the possibility of multiple diseases occurring simultaneously. Although rare, M catarrhalis has the potential to cause a serious bacterial infection. The identification of gram-negative diplococcus in the blood of a patient who has fever and respiratory disease or otitis media should alert the physician to the possibility of the uncommon M catarrhalis as well as the more dangerous N meningitidis. Un caso “strano” per finire Faith, 4 mesi di vita, prematura, viene trasferita dal un Ospedale romano per febbre (MAX: 39.6°C) da 1 settimana e diarrea. E.O.: modica dispnea Tosse secca FR 60 atti/min, Sat.O2: 90-93% Milza e fegato palpabili a 2 cm dall’arco costale. Un caso “strano” Laboratorio: GB: 35.470 (73%) Hb: 7.9 g/dL Trasfusa dopo 2 gg PLT: 335.000 PCR: 18.8 mg/dL D-dimeri: 3500 ng/mL (< 280) EGA: modica alcalosi Feci: Rotavirus ++ Rx torace: refertato nella norma Inizia terapia con Amplital + Gentalyn Un caso “strano” Peggioramento progressivo delle condizioni generali in particolare della dispnea. Si sospetta bronchiolite ed inizia terapia specifica. Dopo 4 gg di terapia: GB: 21000 (N: 76%) PLT: 139.000 PCR: 18 mg/dL ECG e ecocardio: normali Dopo 3 giorni si ripete RX torace che mostra micronoduli diffusi in tutto il parenchima polmonare bilateralmente TC polmonare: Micronoduli diffusi Focolai broncopneumonici lobo inf. Polmone dx e lingula polmone sin. Slargamento profilo mediastinico per incremento volumetrico timo e linfonodi Un caso “strano” Peggioramento progressivo delle condizioni generali, della dispnea, della Sat.O2, FR 85 atti/min, FC 152 atti/min. Febbre persistente fino a 40°C, nonostante terapia con Merrem e Targosid. Sottopopolazioni linfocitarie: CD4 totali (T Helper): 786.7 mmc CD4/CD8: 2.95 (1.5-2.9) Mantoux: neg. Trasferimento In Unità Terapia Intensiva HIV: Positivo BAL: Micobatterio tubercolosi Un caso “strano” per finire Sepsis Bacteremia: the recovery of bacteria in blood culture. When bacteria are not effectively cleared by host defense mechanisms, a systemic inflammatory response is set into motion and can progress independently of the original infection. Sepsis: The systemic response to infection with bacteria, viruses, fungi, protozoa or rickettsiae. Sepsis is one of the causes of systemic inflammatory response syndrome (SIRS). If not recognised or treated early sepsis can progress to severe sepsis, septic shock, multiple organ dysfunction syndrome (MODS) and death. Sepsis Infection Systemic Inflammatory Response Syndrome (SIRS) •Hyper-hypothermia •Tachycardia •Tachypnea •Increased or decreased white blood count Sepsis SIRS + hypotension Severe Sepsis Sepsis with organ dysfunction, hypoperfusion or hypotension, Change in mental status, oliguria, hypoxemia, lactic acidosis Septic shock Severe sepsis + persistent hypotension despite adequate fluid resuscitation Multiple Organ Dysfunction Syndrome (MODS) Homeostasis cannot be maintained without intervention Death