An unusual presentation of brucellosis

Brucellosis is a multisystem disease with protean manifestations. In spite of its prevalence worldwide and endemicity in certain areas, pleural involvement is still a rare presentation of brucellosis and there are only a very few case reports in literature. A case report of pleural brucellosis along with review of literature is being reported.

Keywords: Brucella , pleural disease, pleural effusion

 Brucellosis ^{More Details} is a disease with protean manifestations, and can occur at any age and can affect various organ systems. Pulmonary brucellosis accounts for about 15% of all cases though pleural involvement is particularly rare. ^[1],[2] This case report describes a case of pleural effusion caused by  Brucella ^{More Details}.

A 27-year-old female, with an occupation of traditional cattle and sheep rearing practices and a fondness for consumption of raw and unpasteurized milk products, presented to the out-patient department with chief complaints of fever and myalgia of 3 months duration and dry cough in the preceding 7 days. Fever was higher and accompanied by chills in the morning. No evidence of consistent rise of temperature in the evening, night sweats, or arthralgia was evident.

On examination, evidence of pleural effusion was found in the right lower lung field and spleen was palpable 2 cm below the left costal margin. Her hemogram revealed a total leukocyte count (TLC) of 12,500, with 68% polymorphs, 28% lymphocytes, 2% monocytes and 1% eosinophils.. Her erythrocyte sedimentation rate (ESR) was 35 mm by Westergreen method in the first hour, and Mantoux and Widal tests were negative. Serum Brucella antigen titers were positive (1:160). Rising titers were evident after 1 week (1:320). Polymerase chain reaction (PCR) for brucellosis was positive. The right costophrenic angle was blunted in the chest roentogram. Right pleural effusion with involvement of the horizontal fissure was detected in her contrast-enhanced computed tomography (CECT) chest [Figure 1].

A diagnosis of pleural brucellosis was reached and Rifampicin (750 mg/day) and Doxycycline (200 mg/day) were initiated. The patient demonstrated marked improvement in symptoms within 1 week and her agglutination titers declined in 3 weeks. Combination therapy was continued for a period of 6 weeks.

Brucellosis is a zoonotic disease caused by bacterium of the genus Brucella. It is prevalent in the cattle rearing populations worldwide. The actual incidence of disease is expected to be much higher than estimated because of failure of recognition or reporting of cases in many instances. ^[3]

Brucella infects humans mainly by ingestion of contaminated raw animal products, contact with infected animals and inhalation of infectious particle. ^[4],[5] Isolated reports of transmission via breast milk (from infected mother) and human semen have been reported. ^[6] Brucella is disseminated via hematogenous route with a focal localization in various organ systems like bones, joints, heart and central nervous system. ^[4]

In spite of possible inhalational route of infection, the respiratory complaints in brucellosis are mostly mild and mainly present as “flu like illness” with symptoms of sore throat, tonsillitis and dry cough. More serious manifestations like pleurisy, pneumonia, lung abscess and hilar lymphadenopathy are rare. ^[4] The reports of pleural effusion in brucellosis are limited. ^{[1],[2],[4],[7]} The characteristics of the pleural fluid are its exudative nature with high proteins, low glucose, low pH, elevated adenosine deaminase levels and the predominance of lymphocytes, thus resembling tubercular pleural effusion. ^[4, 8, 9] This proves to be a diagnostic dilemma in endemic regions. Interestingly, there is no available case report of coinfection of both pulmonary tuberculosis and pulmonary brucellosis, despite endemicity. ^[7]

A presumptive diagnosis of brucellosis is made by a positive serology test, which is then confirmed by the isolation of the organism from the blood or tissue. ^[4],[5] PCR is more sensitive and gives quicker results than either blood or tissue culture. PCR does not carry the risk of biohazard inherent to culture. ^[5]

Pleural brucellosis is rarely serious and readily responds to the usual regimens used for the treatment of uncomplicated brucellosis. ^[1],[2],[7] Multidrug antimicrobial regimens are the mainstay of therapy because of high relapse rates associated with monotherapeutic approaches for acute nonfocal brucellosis. Six week therapy with two antibiotics is prescribed, though complex or focal brucellosis necessitates a longer duration of therapy of more than 3 months. ^[1],[5] Pleural brucellosis being treated for 9 weeks or by decortication has also been described. ^[4]

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/1755-6783.77196

[Figure 1]