Pleural fluid

Invasive pathogens either aggressively invade the tissues surrounding the primary site of infeehon or are passively transported around the body in the blood, lymph, cerebrospinal fluid or pleural fluids. Some, espeeially aggressive organisms, do both, setting up a number of expansive seeondary sites of infeehon in various organs. 

Fluids such as tissue aspirates, cyst fluid, bronchial washings, cerebrospinal fluid, pleural fluid, and peritoneal fluid can be examined directly, or they can be centrifuged and the sediment examined by wet mounts or stains (or both), depending on the parasite suspected, as described above for abscesses or tissue. 

Fluid specimens apply to abdominal washings, ascitic fluids, colonic washings, duodenal washings, gastric washings, pleural fluids, pericardial fluids, ovarian cyst fluids, synovial fluids, and sputa. 

The fluid in the lung tissues may drain either toward the pleura or toward the center of the thoracic cavity (Fig. 3.5). The pleural fluid returns through the lymphatics to the central thoracic cavity, where a duct opens into the venous circulation. Thus, the fluid transported from lung tissue is returned to the systemic blood circulation by the lymphatics. Alternatively, fluid can be transported directly by and into the central lymphatic system. 

Drug concentrations in pleural fluid, peritoneal fluid, synovial fluid, aqueous humor, and vitreous humor approach two-thirds of the serum concentration when local inflammation is present. Meningeal and am-niotic fluid penetration, with or without local inflammation, is uniformly poor. Measurement of serum, urine, or cerebrospinal fluid drug levels has not been used clinically. 

Moxalactam readily diffuses into the cerebral spinal fluid (CSF) of patients with and without meningitis (49-52). Distribution of the drug following therapeutic dosages has been determined in CSF (49-52), bile (38,54,55), aqueous humor (53,54), peritoneal fluid, pleural fluid, prostatic fluid, sputum, and several other tissues and fluids. Body fluid and tissue analyses give primarily qualitative data as to the presence or absence of the drug at a particular site, and therapeutic efficacy cannot be predicted from these data. 

Hepatic hydrothorax (C.S. Morrow et al., 1958) is evident during the course of liver cirrhosis with ascites in 0.4-12% of cases. The mean frequency is about 6%, although in two-thirds of the cases, a right-sided effusion (with the author s own patients a bilateral effusion) was ascertained. (66) (s. fig. 16.8) Hepatic hydrothorax is a transudate cell count protein concentration <2.5 g/dl, total protein effusion to serum ratio <0.5, LDH effusion to serum ratio <2.3, serum to pleural fluid albumin gradient >1.1 g/dl. (s. also fig. 16.9) (17, 37, 47, 52 - 54, 66)... 

Spontaneous bacterial empyema is found in 1-2% of patients with cirrhosis and ascites. The diagnosis is based on a positive bacterial test in the pleural fluid and a WBC count in excess of 250/mm (or a negative bacterial culture with a cell count exceeding 500/mm ) - which is analogous to spontaneous bacterial peritonitis. (105) (s. p. 302)... 

Ackermann, Z., Reynolds, T.B. Evaluation of pleural fluid in patients with cirrhosis. J. Clin. Gastroenterol. 1997 25 619—622... 

In procainamide-induced lupus there is an increase in the number of B cells in both blood and pleural fluid to about 80% (normal 10-25%). Concentrations of IL-6 and soluble IL-2R are also increased (46). 

Kennedy L, Harley RA, Sahn SA, Strange C. Talc slurry pleurodesis. Pleural fluid and histologic analysis. Chest 1995 107(6) 1707-12. 

Moulton JS, Benkert RE, Weisiger KH, Chambers JA. Treatment of complicated pleural fluid collections with image-guided drainage and intracavitary urokinase. Chest 1995 108(5) 1252-9. 

Available studies suggest that penetration of the newer quinolones into all extravascular sites (large-volume spaces i.e., ascites, pleural fluid, etc.), secretory fluids (urine, prostatic secretions, sputum, etc.), barrier fluids (CSFL), and whole tissues is high relative to the penetration reported for most other categories of antimicrobial agents, particularly, the penicillins, cephalosporins, and aminoglycosides... 

Cephalosporins distribute into most body fluids and tissues, including pleural fluid, synovial fluid, pericardial fluid and urine. Cephalosporins distribute into milk, but therapeutic concentrations are not reached following systemic administration at accepted dose rates. Cephalosporins cross the placenta but do not appear to cause adverse effects in the fetus. Their penetration into cortical and cancellous bone is usually adequate. Most cephalosporins penetrate poorly into the aqueous humor, accessory sex glands and CSF. Cephalosporins have typically low values in horses 0.191/kg for cefazolin, 0.151/kg for cefa-lotin, 0.171/kg for cefapirin, 0.41/kg for cefradine and 0.121/kg for cefoxitin. 

Lineomycin hydrochloride occurs as the monohydiate. a white, crystalline solid that is stable in the dry state. It is readily soluble in water and alcohol, and its aqueous solutions arc stable at room temperature. It is degraded slowly in acid solutions but is absorted well from the ga.strointesti-nal tract. Lineomycin diffuses well into peritoneal and pleural fluids and into bone. It is excreted in (he urine and the bile. It is available in capsule form for oral administration and in ampules and vials for parenteral administration. 

Available through COC or LRN. Cell block obtained by centrifugation of pleural fluid. Serologic testing available at COC may be an additional diagnostic technique. 

The proteins most amenable to routine laboratory evaluation die those in blood, urine, CSF amniotic fluid, saliva, feces, and peritoneal or pleural fluids. With few exceptions, the proteins found in all of these are derived from blood plasma. The following discussion is limited to (1) the most abundant plasma proteins, (2) changes of their concentrations in the most accessible body fluids, and (3) a few of the analytical techniques used to measure them. 

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