Subcostal lump an unusual presentation of infra-pulmonary effusion.
Pleura and pleural cavities are the sites of a variety of medical and surgical disorders. Various systemic and pleuropulmonary diseases commonly manifest as pleural effusion. Infra-pulmonary effusion which is usually a roentgenological diagnosis, invariably presents as a clinical quiz. Its occurrence as a subcostal lump is even rarer. We are presenting a case of infrapulmonary effusion who presented as a subcostal lump of gradual onset. Such an occurrence is yet to be reported in the available Indian literature.
M. K., a 65 year old Hindu male was admitted in the Medical Unit of S. M. S. Medical College and Hospital, Jaipur, on 17th July, 1979, with the complaints of localised dull ache, gradually increasing right hypochondric and subcostal swelling and weight loss since 2 months. There was no history of jaundice, bleeding per rectum, trauma, surgery, tuberculosis; and handling cattles. Systemic examination revealed pallor and infra-abdominal lump of. 10" x 6" in size in the right subcostal, epigastric, paraumbilical and lumbar region and the upper border of the lump was in continuation with the costal margin, while the lower border was sharp, regular, well defined, firm and smooth. The lump freely moved with respiration. Liver dullness was present in the right 5th intercostal space in the mid-clavicular line. There was no pulsation, hydatid thrill, rub or bruit over the swelling. Other systemic examination did not reveal any abnormality.
Haemoglobin was 7.8 g/dl. Total leucocyte count was 7500/cmm. with P-60%, L-38%, E1%; and M-1%. ESR was 100 mm/1st hour (Westergren). No malarial parasites were seen. Blood urea nitrogen and creatinine were 10% mg and 1 mg% respectively. Total serum protein level was 5.4 g% with albumin of 3.2 g%, and an A/G ratio of 1.5 : 1. Liver function tests were within normal limits with S.G.O.T. and S.G.P.T. levels of 22 and 141 units respectively. Serum bilirubin was 0.6 mg%; and serum alkaline phosphatase was 4.2 K.A. Units. Urine and stool examination showed nothing abnormal, ECG did not show any abnormality. Casoni's test was negative but Mantaux test was strongly positive (1:1003 dilution) .
Fluoroscopy of the chest revealed obliteration of the right costophrenic angle with normal diaphragmatic movements. X-ray abdomen in flat position was normal. P-A view of the X-ray chest showed obliteration of the right costophrenic angle and also revealed displacement of maximum convexity of the right dome of the diaphragm near the chest wall [Fig. 1].
Lateral view of the X-ray chest showed an angulation of the anterior 1/3 and middle 1/3 of the dome of the diaphragm on the right side [Fig 2].
Liver scanning showed displacement of liver uptake shadow downwards with a cold area in the right hypochondrium.
Provisional diagnosis of infrapulmonary effusion was made and pleural paracentesis of 1800 ml of straw coloured exudate was done, with the result that the subcostal lump regressed. Patient was discharged with anti-tubercular treatment and steroids. Follow up of the case revealed constant improvement without recurrence.
Most of the pleural effusions are initially infrapulmonary but as the amount of fluid increases it occupies the major fissure and parietal pleural space.,  The extension of the fluid mainly depends upon capillary attraction, viscosity and surface tension of the fluid and elastic recoil of the lung.
Roentgenological diagnosis of infrapulmonary effusion is made by following criteria:
(1) Elevation of the hemi-diaphragm.
(2) Shift of the maximum convexity of the dome of diaphragm near the lateral chest wall.
(3) Shallow costophrenic angle.
(4) Development of fluid density between the gastric air bubble and inferior surface of lung.
(5) Angulation at anterior 1 3rd and middle 1/ 3rd of dome of diaphragm in place of normal smooth curve' (in lateral view).
(6) Extension of fluid along longiudinal fissure making an angle with the diaphragm-Rodegibralter sign.
(7) Concavity upwards at the posterior margin of diaphragm.
(8) Supine view shows widening of the paravertebral gutter with the generalised haziness of the lung fields.
Our case presenting as a subcostal lump with no respiratory complaints but positive Mantaux test, raised ESR, obliterated costophrenic angle and shift of maximum curvature of diaphragm near the lateral chest wall suggested us a diagnosis of infrapulmonary effusion of tubercular origin. This was later confirmed by the regression of the lump after pleural paracentesis of 1800 ml exudative fluid. Occurrence of subcostal lump in infrapulmonary effusion is explained by inversion of the dome of diaphragm by fluid pressure which gives paradoxical movement on deep inspiration. However, in our case, we did not observe paradoxical movement which was identical to the observation of Pierce.