Brucellosis: unusual presentations in two adolescent boys

Download Brucellosis: unusual presentations in two adolescent boys

Post on 11-Jul-2016

212 views

Category:

Documents

0 download

Embed Size (px)

TRANSCRIPT

  • Introduction

    Brucellosis (Bangs disease, undulant fever, or Malta fe-ver) is a zoonotic infection, but relatively rare humandisease in the United States, with approximately 1 re-ported case per 2 million population [1]. It usually is amild or asymptomatic disease. The natural animal reser-voir hosts for the bacteria are cattle for Brucella abortus,goats and sheep for Brucella melitensis, swine for Bru-cella suis, and dogs, foxes, and coyotes for Brucella can-is. The disease has worldwide distribution, affectsindividuals of all ages, and may have protean organ-sys-tem manifestations. Aortic and peripheral aneurysmshave been described involving adult patients [2], butnone in children. Pulmonary involvement is especiallyrare in children [3]. We report one adolescent boy withcardiovascular involvement and another adolescentboy with cranial, intracranial, and pleuropulmonary in-volvement with brucellosis.

    Case report 1

    A 15-year-old boy complained of chronic fatigue, palpitations,light-headedness, and a 20-lb. (ca. 9 kg) weight loss in 6 months.He also had a pulsatile mass in the right calf. Physical examina-tion revealed a continuous 3/6 cardiac murmur that radiated tothe left axilla, and bilateral pulsatile non-tender calf masses. In-fectious disease workup for endocarditis revealed WBC 4,200/mm, 8 sets of negative blood cultures bacteria and fungi. Echocar-diography revealed multiple vegetations and aortic valve regurgi-tation. Gadolinium-enhanced magnetic resonance angiography(MRA) of the chest and extremities showed aneurysms of theright posterior tibial artery and the left peroneal artery (Fig.1).The patient underwent a Ross procedure (pulmonary autograftfor aortic root and valve replacement, reimplantation of the rightand left coronary arteries with pulmonary homograft reconstruc-tion of the right ventricle to pulmonary artery connection) forthe aortic vegetations. Seven days later, Duplex sonography ofthe lower extremities showed complete thrombosis of the rightposterior tibial artery aneurysm and partial thrombosis of theleft peroneal aneurysm. The patient underwent repair of the leftperoneal artery aneurysm, which had a neck as was demonstratedon the MRA. Follow-up Brucella canis serology titers on the sur-gical pathology specimens were elevated. On further questioning,

    Peter PiampianoMichael McLearyLionel W.YoungDonald Janner

    Brucellosis: unusual presentationsin two adolescent boys

    Received: 4 August 1999Accepted: 7 December 1999

    P.Piampiano M. McLeary ()) L. W. YoungDepartment of Radiology,Division of Pediatric Radiology,Loma Linda University ChildrensHospital, 11 234 Anderson Street,Loma Linda, CA 92354, USA

    D. JannerDivision of Pediatric Infectious Disease,Loma Linda University Medical Center &Childrens Hospital, Loma Linda,California, USA

    Abstract Two boys presented withvariable signs and symptoms of in-fectious disease that challenged di-agnosis. One of the two patients hadaortic valve vegetations and lowerextremity aneurysms, and the otherhad calvarial osteomyelitis, epiduralabscess, pleural effusions, and pul-monary nodules. Only after a bat-tery of bacterial and fungalagglutination tests was the unsus-pected diagnosis made in each ofbrucellosis from Brucella canis.

    Pediatr Radiol (2000) 30: 355357 Springer-Verlag 2000

  • the boy stated that he had a sick and skinny dog. The patientwas treated with intravenous antibiotics for 1 month and is cur-rently asymptomatic.

    Case report 2

    A 14-year-old boy had a 1-month history of weakness, fatigability,dry cough, intermittent fever and chills, progressively worseningshortness of breath, and pleuritic chest pains. On physical exami-nation, the temperature was103F, and a 2-cm non-fluctuant, non-erythematous, non-tender mass was present over the left mid-fore-head area. His WBC 2,400/mm, segs 58, bands 17, lymphocytes 20.Chest radiography and CT scan demonstrated multiple bilateral

    356

    Fig.1 Case 1. FISP 3D-contrasted enhanced MIP reconstructionsof the lower extremities during the arteriovenous phase demon-strated saccular aneurysms of the right posterior tibial artery andleft peroneal artery. Necks are evident with both aneurysms (ar-rows). The arterial phase of the MRA (not shown) did not demon-strate the aneurysm well, presumably secondary to turbulentdephasing and mixing of the enhanced and non-enhanced blood

    c

    b

    a

    Fig.2ac Case 2. a Contrast-enhanced axial CT scan of the chestshowed multiple peripheral cavitating nodules in the anterior andposterior segments of the right upper lobe and another in the api-coposterior segment of the left upper lobe. Bilateral pleural effu-sions were also present. b CT scan of the head utilizing bonewindows demonstrated an erosive defect involving the inner tableof the left side of the frontal bone, as well as an adjacent small epi-dural component and a larger subcutaneous soft tissue mass.c Contrast-enhanced CT scan of the head demonstrated a smallleft frontal epidural low density area with peripheral enhancementrepresenting an epidural abscess

  • cavitating peripheral pulmonary nodules, and pleural effusionswithout evidence of adenopathy (Fig.2a). CT scan of the headshowed an erosive lesion involving the inner table of the left fron-tal bone with an underlying loculated epidural fluid collection andadjacent subcutaneous mass (Fig.2b,c). Gram stain of the fore-head aspirate showed multiple polymorphonuclearleukocytes andgram-positive cocci. He underwent craniotomy incision and drain-age of the left frontal epidural abscess. Subsequently, Brucella can-is titers were elevated. Doxycycline and rifampin therapy wasfollowed by progressive improvement, and the boy is currently as-ymptomatic.

    Discussion

    Brucella is a non-motile, nonencapsulated, gram-nega-tive, aerobic bacillus that grows slowly in culture medi-um [1]. Brucella is transmitted from animals to humansvia three main routes: the digestive tract (eating unpas-teurized milk or contaminated meat); by direct contactwith infected tissues (blood, lymph, conjunctiva, orbroken skin); or by the respiratory system (inhalationby laboratory personnel of the live virus or clinical iso-lates) [4]. Brucellosis is a multisystem disease with non-specific manifestations that may have an acute,subacute, or chronic clinical course. The classic presen-tation is one of malaise, chills, periodic nocturnal fever(undulant fever) with progression to chronic illnesscharacterized by body aches, headache, anorexia, andsubstantial weight loss. The primary site of localized in-fection is within the reticuloendothelial cells, with the

    musculoskeletal system being the most frequent site[4].

    Brucellosis is a rare cause of peripheral arterial aneu-rysms: although cases of aortic aneurysm and peripheralaneurysms have previously been reported [2]. In case re-port 1, brucellar endocarditis and extensive aortic vege-tations provided a clear origin for septic emboli and thedevelopment of peripheral mycotic aneurysms.

    Approximately 16% of brucella infections occurwith pulmonary involvement [2]. Pulmonary consolida-tion, bronchitis, parenchymal nodules, hilar adenopa-thy, and pleural effusions have all been reported withbrucellosis [3]. Although pulmonary involvement iswell documented, pulmonary disease is uncommon andeven more unusual in children with only 4 of 1,300 chil-dren with pulmonary compilations due to brucellosis,in one study, and only 9 of 1,500 patients in a secondstudy.

    Musculoskeletal involvement by brucella is well doc-umented. Osteomyelitis, especially of the spine, is com-mon and can occur in focal or diffuse forms. Arthritis isalso common, but myositis and osteomyelitis of thelong bones are rare [5]. Case report 2 concerns even rar-er brucellar osteomyelitis of the frontal bone with epi-dural abscess.

    In view of increased world travel and the potentialfor Brucella species to cause unexplained or unusual ill-ness involving almost any organ, brucellosis should beconsidered when faced with a difficult infectious diag-nostic problem.

    357

    References

    1. Murray PR (1998) Bordetella, Fran-cisella, and Brucella. In: Brown M (ed)Medical microbiology. Mosby, St Louis

    2. Patel PJ, Al-Suhaibani H, Al-Aska AK,et al (1988) The chest radiograph inbrucellosis. Clin Radiol 39: 3941

    3. Gelfand MS, Kaiser AB, Dale WA(1989) Localized brucellosis: poplitealartery aneurysm, mediastinits, demen-tia, and pneumonia. Rev Infect Dis 2:783788

    4. Trujillo IZ, Zavala AN, Caceres JG,et al (1994) Brucellosis. Infect Dis ClinNorth Am 8: 225241

    5. Al-Shahed MS, Sharif HS, Haddad MC,et al (1994) Imaging features of muscu-loskeletal brucellosis. Radiographics14: 333348