Unusual Presentation of Brain Abscess in Unrepaired Tetralogy of Fallot

Unusual presentation of brain abscess in unrepaired tetralogy of Fallot.

Abstract

The association between unrepaired congenital heart disease (CHD) and its predisposition to intracranial complications are well known. We herein report one such case of brain abscess in a patient with tetralogy of Fallot who presented with only headacheof one week duration without any neurologic deficits. Patient underwent phlebotomy with an initial diagnosis of hyperviscocity syndrome. However due to persistence of headache, patient underwent computed tomography (CT) of head which revealed a large, well defined ring enhancing intracerebral abscess with minimal mass effect.

Key words: Tetralogy of Fallot, Intracranial complications, Brain abscess.

Introduction

Unrepaired CHD isan important risk factor for the development of intracranial abscess but for its rarity in adults.1It is usually diagnosed when a patient presents with symptoms of high grade fever, throbbing headache, altered sensorium, focal neurologic deficit or seizures.2 Hyperviscocity syndrome is more likely a possibility when patient presents with only headache without other neurologic symptoms.3Hence there may be significant delay in diagnosing intracerebral abscess in adults with congenital heart disease in presence of atypical symptoms.

Case Report:

A male patientaged 27years diagnosed of having tetralogy of Fallot presented with history of headache of one week duration.There was no history of fever,vomiting,altered sensorium, loss of consciousness,convulsions or head injury.There was no other significant illness in the past. On examination he hadgrade 3 clubbing (Fig-1);intense cyanosiswith oxygen saturation of 86% at room air and body mass index was 13.8kg/m2. His pulse rate was 84beats/min andregular with blood pressure of 110/70mmHg in all the four limbs. Jugular venous pressure was not raised.His apex beat was felt in 5th intercostal space half an inch medial to midclavicular line with left parasternal heave.On auscultation, 1st heart sound was normal and 2nd heart sound was single. A grade 4/6 pansystolic murmur was audible all over the precordium.Neurological examination was essentially normal without any focal deficits.Respiratory and Gastrointestinal systems were normal. Preliminary investigations revealedpolycythaemia with haemoglobin of 27gm/dl,total white blood cells count of 7,700cells/dl with normal differential counts. Erythrocyte sedimentation ratewas 5mm in 1st hr. ECG showed Right axis deviation and Chest X-ray was suggestive of Boot Shaped Heart (Fig-2).Echocardiography showed evidence of ventricular septal defect,over riding of aorta,right ventricular hypertrophy and right ventricular outflow tract obstruction consistent with Tetralogy of Fallot (Fig-3, 4). There was no evidence of vegetation.In view of only headache without any other neurological symptoms, a possibility of hyperviscocity syndrome was considered and patient was treated with phlebotomy for next 3 consecutive days. However patient continued to have temporal headache without any new symptoms of fever,vomiting,convulsions,ear discharge or neurological symptoms. A regular neurological assessmentdid not reveal any focal deficit. Fundoscopyshowedhyperaemic disc without papilledema.CT of headdone on fourth day revealeda moderate sized (40mm), rounded, hypodense ring enhancing lesion involving the right posterior parietal lobe with perilesional oedema with minimal mass effect suggestive of cerebral abscess (Fig-5).Patient was started onIntravenousbroad spectrum antibiotics,antiedema measures & prophylactic antiepileptic drugs.He was planned for surgical intervention. Incidentally patient was found to bepositive forhepatitis Bsurface antigen. Further evaluation showed IgG anti-HbCAg positive and HbEAg negative. Patient didn’t undergo surgical intervention due to logistical reasons.

Discussion

A peak incidence of intracranial abscess is seen in the age group of 4 to 7 years with TOF being the most common underlying cardiac anomaly predisposing for brain abscess.4 It is usually diagnosed when a cyanotic heart disease patient presents with typical symptoms of high grade fever, headache, focal neurologic deficits and seizures. The diagnosis is further strengthened by imaging studies which demonstrates a welldefined ring enhancing lesion with perilesional oedema.5The brain abscess occurs at junction of the grey and white matter and is due to various reasons like septic cerebral embolism, contiguous extension of infection from otitis media and facial or dental infection.6 Haematogenous spread of infection can result in brain abscess at multiple location.7 Two preconditions prerequisitefor the occurrence of brain abscess include bacteraemiain the cerebral circulation and a focal zone of ischemia in brain parenchyma.8,9The most common organisms implicated are Streptococcus milleri, Staphylococcus, other Streptococcus and Haemophilus species.10, 11, 12Treatment includes aspiration of abscess along with appropriate antibiotic therapy.Resection of the abscess is rarely required. The rarity in our case was patient presented only with headache of one week duration prior to admission. He never had neurologic symptoms or signs for which initial diagnosis of hyperviscocity syndrome was considered and initiated with phlebotomy. Patient remained symptomatic despite phlebotomy till the fourth day of admission when CT brain was considered which revealed brain abscess. Interestingly patient was positive for hepatitis B surface antigen the cause of which could not be ascertained.

Conclusion

Cyanotic congenital heart disease patient presenting with history of headache with or without fever and other neurological symptomswarrants an imaging studies at the earliest to look for intracranial pathology. Delay in recognition of brain abscess will prolong the initiation of definitive therapy especially in presence of atypical presentation. This will even worsen the already existing brain damage. This should be followed by total correction of the cardiac defect if possible to prevent further complication.

References:

1.Chong Won Sung MD, Jae-Hun Jung MD, Sang-Hak Lee MD et al.Brain Abscess in an Adult With Atrial Septal Defect. Clinical Cardiology, April 2010, Volume 33, Issue 4,pages E51–E53.

2.Perloff JK, Child JS, Aboulhosn J. Congenital heart disease in adults, WB Saunders, Philadelphia 2009.

3. Loomba RS, Leavitt JA, Cetta F.Headache and Papilledema in an Adult with Cyanotic Congenital Heart Disease: The Importance of Fundoscopic Evaluation Rather Than Phlebotomy. Congenit Heart Dis. 2011 Nov 9. doi: 10.1111/j.1747-0803.2011.00586.x. [Epub ahead of print]

4.Fischbein CA, Rosenthal A, Fischer EG, et al. Risk factors of brain abscess in patients with congenital heart disease. Am J Cardiol 1974; 34:97.

5. Carpenter J, Stapleton S, Holliman R Retrospective analysis of 49 cases of brain abscess and review of the literature. Eur J Clin Microbiol Infect Dis. 2007 Jan; 26(1):1-11.

6. Takeshita M, Kagawa M, Yonetani H, Izawa M et al: Risk factors for brain abscess in patients with congenital cyanotic heart disease. Neurol Med Chir (Tokyo) 1992, 32:667–670,

7. Kumar K, Neurological complications of congenital heart disease. Indian J Pediatr. 2000 Apr;67(4):287-91.

8.Mizuo Kagawa, Mikihiko Takeshita,Seiji Yatō, Kōiti Kitamura. Brain abscess in congenital cyanotic heart disease.Journal of NeurosurgeryJune 1983 / Vol. 58 / No. 6 / Pages 913-917

9.Mehnaz A, Syed AU, Saleem AS, Khalid CN. Clinical features and outcome of cerebral abscess in congenital heart disease.J Ayub Med Coll, Abbottabad. 2006 Apr-Jun; 18(2):21-4.

10. Basit AS, Ravi B, Banerji AK, Tandon PN: Multiple pyogenic brain abscesses: an analysis of 21 patients. J Neurol Neurosurg Psychiatry 52:591–594, 1989.

11. Carpenter J, Stapleton S, Holliman R. Retrospective analysis of 49 cases of brain abscess and review of the literature. Eur J Clin Microbiol Infect Dis. 2007 Jan; 26(1):1-11.

12. Atiq M, Ahmed US, Allana SS, Chishti KN. Brain abscess in children. Indian J Pediatr. 2006 May; 73(5):401-4

FIGURE LEGENDS:

Fig-1:Showing evidence of drumstick appearance of fingers.

Fig-2: Chest X-ray showed evidence of Boot shaped heart (“Cour en Sabot”), uplifting of cardiac apex, absence of main pulmonary artery & decreased pulmonary vasculature.

Fig-3: Parasternal long axis showing large subpulmonic VSD with overriding of aorta.

Fig-4: Parasternal short axis view showing high gradient of 72.3 mmHg across right ventricular outflow tract.

Fig-5: Computed tomography of the brain showing well defined ring enhancing lesion with perilesional oedema with minimal mass effect suggestive of cerebral abscess.