Lung abscess 2452670 215326943 2008-05-27T18:38:18Z DOI bot 6652755 Citation maintenance. You can [[WP:DOI|use this bot]] yourself! Please [[User:DOI_bot/bugs|report any bugs]]. {{Infobox_Disease | Name = {{PAGENAME}} | Image = Lung abscess.jpg| Caption = Lung section showing apical abscess| DiseasesDB = 7607 | ICD10 = {{ICD10|J|85||j|85}} | ICD9 = {{ICD9|513.0}} | ICDO = | OMIM = | MedlinePlus = | eMedicineSubj = med | eMedicineTopic = 1332 | MeshID = D008169 | }} '''Lung abscess''' is [[necrosis]] of the [[pulmonary]] tissue and formation of cavities (more than 2 cm)<ref>{{cite journal |author=Bartlett JG, Finegold SM |title=Anaerobic pleuropulmonary infections |journal=Medicine (Baltimore) |volume=51 |issue=6 |pages=413–50 |year=1972 |pmid=4564416 |doi=}}</ref> containing necrotic debris or fluid caused by [[microbial]] infection. This pus-filled cavity is often caused by aspiration, which may occur during altered consciousness. [[Alcoholism]] is the most common condition predisposing to lung abscesses. Lung Abscess is considered '''primary'''(60%<ref name="medscape">{{cite web |url=http://www.medscape.com/viewarticle/534860 |title=Pneumonia and Other Pulmonary Infections: Lung Abscess, Medscape |accessdate=2007-06-20 |format= |work=}}</ref>) when it results from existing lung [[parenchymal]] process and is termed '''secondary''' when it complicates another process e.g. [[Blood vessel|vascular]] [[emboli]] or follows rupture of [[extrapulmonary]] [[abscess]] into lung. == Causes == ;Conditions contributing to lung abscess *Aspiration of [[oropharyngeal]] or [[gastric]] secretion *Septic emboli *[[Necrotizing]] [[pneumonia]] *[[Vasculitis]]: [[Wegener's granulomatosis]] *Necrotizing [[tumors]]: 8% to 18% are due to [[neoplasms]] across all age groups, higher in older people; primary [[squamous carcinoma]] of the lung is the commonest. ;Organisms In the post-antibiotic era pattern of frequency is changing. In older studies anaerobes were found in up to 90% cases but they are much less frequent now<ref>{{cite journal |author=Bartlett JG |title=The role of anaerobic bacteria in lung abscess |journal=Clin. Infect. Dis. |volume=40 |issue=7 |pages=923–5 |year=2005 |pmid=15824980 |doi=10.1086/428586}}</ref>. *[[Anaerobic bacteria]]: [[Peptostreptococcus]], [[Bacteroides]], [[Fusobacterium]] species, *[[Microaerophilic]] [[streptococcus]] : ''[[Streptococcus milleri]]'' *[[Aerobic bacteria]]: [[Staphylococcus]], [[Klebsiella]], [[Haemophilus]], [[Pseudomonas]],[[Nocardia]], [[Escheria coli]], [[Streptococcus]], [[Mycobacteria]]<ref name="pmid10084487">{{cite journal |author=Hirshberg B, Sklair-Levi M, Nir-Paz R, Ben-Sira L, Krivoruk V, Kramer MR |title=Factors predicting mortality of patients with lung abscess. |journal=Chest |volume=115 |issue=3 |pages=746–50 |year=1999 |pmid=10084487 |doi=}}</ref> *[[Fungus|Fungi]]: [[Candida (genus)|Candida]], [[Aspergillus]] *Parasites: [[Entamoeba histolytica]], == Symptom and sign == Onset of symptoms is often gradual, but in necrotizing staphylococcal or gram-negative bacillary pneumonias patients can be acutely ill. [[Cough]], fever with shivering and [[night sweats]] are often present. Cough can be productive with foul smelling [[purulent]] [[sputum]] (≈70%) or less frequently with blood (i.e. [[hemoptysis]] in one third cases) <ref name="Moreira">{{cite journal |author=Moreira Jda S, Camargo Jde J, Felicetti JC, Goldenfun PR, Moreira AL, Porto Nda S |title=Lung abscess: analysis of 252 consecutive cases diagnosed between 1968 and 2004 |journal=Jornal brasileiro de pneumologia : publicaça̋o oficial da Sociedade Brasileira de Pneumologia e Tisilogia |volume=32 |issue=2 |pages=136–43 |year=2006 |pmid=17273583 |doi=}}</ref>. Affected individuals may also complaint chest pain, shortness of breath, [[lethargy]] and other features of chronic illness. Patients are generally [[cachexia|cachectic]] at presentation. Finger [[clubbing]] is present in one third of patients<ref name="Moreira"/>. Dental decay is common especially in alcoholics and children. On examination of chest there will be features of consolidation such as localised dullness on [[percussion]], [[Breath sounds|bronchial breath sound]] etc. == Diagnosis == ;Chest Xray and other imaging studies Abscess is often [[unilateral]] and single involving posterior segments of the upper lobes and the apical segments of the lower lobes as these areas are gravity dependent when lying down. Presence of air-fluid levels implies rupture into the [[bronchial tree]] or rarely growth of gas forming organism. ;Laboratory studies Raised inflammatory markers ( high [[Erythrocyte sedimentation rate|ESR]], [[C-reactive protein|CRP]]) are usual but not specific. Examination of sputum is important in any pulmonary infections and here often reveals mixed flora. [[Respiration (physiology)|Transtracheal]] of [[bronchus|Transbronchial]] (via bronchoscopy) aspirates can also be cultured. Fibre optic [[bronchoscopy]] is often performed to exclude obstructive lesion; it also helps in bronchial drainage of pus. == Management== Broadspectrum [[antibiotic]] to cover mixed flora is the mainstay of treatment. Pulmonary physiotherapy and postural drainage are also important. Surgical procedures are required in selective patients for drainage or pulmonary resection. == Complications == Rare now a days but include spread of infection to other lung segments, [[bronchiectasis]], [[empyema]], and [[bacteraemia]] with [[metastasis|metastatic]] infection such as [[brain abscess]]<ref name="medscape"/>. == Prognosis == Most cases respond to antibiotic and prognosis is usually excellent unless there is a debilitating underlying condition. Mortality from lung abscess alone is around 5% and is improving. ==See also== *Other chronic lung infections **[[Empyema]] **[[Bronchiectasis]] *[[Abscess]] *[[Pleural effusion]] ==External links== * [http://www.merck.com/mrkshared/mmanual/section6/chapter74/74a.jsp Merck] * {{Chorus|02036}} ==References== {{reflist}} {{Respiratory pathology}} [[Category:pulmonology]] [[es:Absceso pulmonar]] [[nl:Longabces]] [[pl:Ropień płuc]] [[ru:Абсцесс лёгких]] [[fi:Keuhkopaise]]