MICROBIOLOGY SECTION - CASE REPORT |
|
|
|
Year : 2008 | Volume
: 51
| Issue : 1 | Page : 151-153 |
|
Nocardia brain abscess in a diabetic patient |
|
Prithwiraj Chakrabarti, Sitansu Sekhar Nandi, Subhash Kumar Todi
Department of Microbiology, Advanced Medicare Research Institute (AMRI) Hospitals, Kolkata, India
Click here for correspondence address and email
|
|
 |
|
Abstract | | |
Brain abscess due to disseminated nocardia infection is an acute medical emergency among immunocompromised patients. We report a case of rapidly progressive nocardia brain abscess in an apparently healthy diabetic individual. The close similarity of the radiological features with those of malignancy and tuberculosis may delay the diagnosis of central nervous system (CNS) nocardiosis. A high index of suspicion and early intervention like stereotactic brain biopsy remain the cornerstone to increase the chance of positive clinical outcome. Keywords: Brain abscess, nocardia, stereotactic brain biopsy
How to cite this article: Chakrabarti P, Nandi SS, Todi SK. Nocardia brain abscess in a diabetic patient. Indian J Pathol Microbiol 2008;51:151-3 |
Introduction | |  |
Nocardia has become an emerging opportunistic infection among immunocompromised patients. Dissemination most commonly leads to CNS disease, with a very high fatality rate. The level of immunocompromize may not always correlate with disease severity; many other epidemiological factors are closely linked with primary or disseminated nocardiosis. The increasing incidence of nocardiosis demands high clinical suspicion when any CNS lesion presents with a differential diagnosis of malignancy or tuberculosis. Here we report a case of fatal nocardia brain abscess in a diabetic patient.
Case History | |  |
A 54-year-old man was admitted to Advanced Medicare Research Institute, Kolkata, India, with seven days' history of headache, vomiting, unsteadiness and fall, along with visual disturbances. He was a known case of diabetes for the last eight years.
On physical examination, he was normotensive, and his temperature was 38°C. Central nervous system examination revealed mild disorientation, left hemianopia, left hemiparesis and left hypoanesthesia. The peripheral blood leukocyte count was 11,600/mm 3 with 84% polymorphonuclear (PMN) cells and 16% lymphocytes. ESR (85 mm/hour) and blood sugar (345 mg/dL) values were elevated. Platelet count, urea, creatinine, electrolytes (Na + , K + , Cl−, HCO 3−) and LFT values were within normal limits.
CT scan of the brain showed an irregularly enhancing hypodense SOL in the right parieto-occipital region. The patient was immediately put on insulin, fluids, IV piperacillin-tazobactam and IV metronidazole. Blood sugar was controlled, but the patient developed seizures twice during the following day. A right-sided basal infiltrate was noted on chest x-ray. CT scan of the thorax showed a right lower lung basal segment subpleural nodular lesion and infiltration in left upper lung and right middle lobe. Seizure was controlled by IV mannitol, steroid and phenytoin, and ATD was started empirically as FNAC of the subpleural chest lesion was technically risky. Two days later the patient was still febrile, with an elevated leukocyte count of 24,500/mm 3 with 90% PMN cells. Repeated attacks of seizure started and the patient became decerebrated. The bilirubin level was elevated to 2.9 mg/dL, and ATD was stopped.
MRI of the brain showed two large enhancing necrotic lesions with edema and mass effect [Figure - 1]. Craniotomy was done in the right parieto-occipital region, and thick green pus was aspirated with partial excision of the lesion. Histopathology of excised tissue showed acute fibrinous inflammatory exudates with predominantly neutrophilic population and areas of necrosis. Gram stain of the pus showed tiny gram-positive branching filaments and coccoid fragments with plenty of pus cells. Ziehl-Neelsen stain was negative for acid-fast bacilli. A modified Ziehl-Neelsen stain with 1% H 2 SO 4 showed large number of typical pink branching filamentous structures, suggesting nocardia species [Figure - 2]. Characteristic yellow wrinkled colony appeared within 72 hours when cultured on blood and chocolate agar. Growth of nocardia asteroids complex was confirmed by microscopy, subculture on Loewenstein-Jensen media, paraffin baiting technique and biochemical tests. Blood cultures showed no growth after seven days of incubation.
Intravenous amikacin and cotrimoxazole DS 8 tablets per day given through nasogastric tube were started (IV cotrimoxazole is not routinely available), and marked clinical improvement was observed on subsequent three days. Cotrimoxazole was replaced by meropenem due to systemic side effects like thrombocytopenia. On the sixth postoperative day, his clinical condition deteriorated and soon he developed bleeding from tracheostomy site with an unexplained thrombocytopenia (platelet count 60,000/mm 3 ) and high FDP (800 ng/mL). A repeat blood culture was sterile; culture from tracheostomy wound grew Candida albicans . Finally on the ninth postoperative day, he expired.
Discussion | |  |
The diagnosis of brain abscess with subacute onset is always challenging in cases where a peripheral septic focus is not conspicuous. The consideration of the possibility of CNS tuberculosis and malignancy may cause delay in opting for early intervention and more invasive procedures like brain biopsy. Routine use of steroid to reduce cerebral edema may worsen the condition. CT scan is very effective in demonstrating the lesion, but an early MRI and stereotactic brain biopsy remain the cornerstone for definitive diagnosis and management. [1]
In the present case, a subacute onset with SOL in the brain and chest infiltrate initially went in favor of a clinical diagnosis of tuberculosis. A nocardial etiology was first suspected on gram staining of the pus aspirated by brain biopsy. Although appropriate antinocardial antibiotics were started immediately following diagnosis, with some definite postoperative improvement, finally the patient could not be saved due to development of disseminated intravascular coagulopathy probably due to absorbed toxins or concomitant infections like candida that might be aggravated by cotrimoxazole toxicity.
CNS nocardiosis is a rare clinical entity, where diagnostic delay can always lead to fatal outcome. Like bacterial infection, nocardia also forms rapidly developing brain lesion. Although nocardia asteroids complex primarily causes lung disease, dissemination is favored by various debilitating patient-factors like diabetes and chronic lung disease. Disseminated infections with more virulent newly identified species like N. farcinicia , N. nova and N. pseudobraziliensis have also been reported. [2]
Clinical and radiological features are not pathognomonic for nocardial infection; thus, smear and culture remains the principal mode of diagnosis. [2] Nocardia is easily diagnosed by modified acid-fast staining with 0.5-1% H 2 SO 4 as decolorizing agent. Gram staining is extremely important because the organism is usually missed with routine acid-fast staining (with 20% H 2 SO4 ), and culture may require prolonged incubation before appearance of typical colonies. Nocardia typically grows within two to seven days on blood agar, chocolate agar and LJ media; but colistin-nalidixic acid agar, modified Thayer-Martin agar and buffered charcoal-yeast extract (BCYE) agar are preferred when the specimen is contaminated. [3] Thus, confirmation requires simple modification of routine techniques that demand high index of clinical suspicion.
Speciation is required for epidemiological purposes; prognostic correlation with different species is still under evaluation. Speciation may not always be possible in routine laboratories. Paraffin-baiting technique may help to isolate nocardia asteroids complex. [4] Complicated phenotypic tests or molecular methods are required for further identification. [5]
Though most isolates are susceptible to cotrimoxazole, combination with one or more drugs may favor clinical outcome in disseminated nocardiosis, particularly with cerebral involvement. [6] Moreover, clinical use of cotrimoxazole in critically ill patients is restricted due to systemic side effects and less availability in parenteral form. Although resistance is not widespread, CLSI (formerly NCCLS) recommends drug sensitivity for refractory cases. Carbapenems, aminoglycosides, minocyclines and linezolid have been found to very effective in many clinical situations. [6],[7]
In conclusion, nocardiosis is a clinical entity which should be kept in the differential diagnosis of any brain abscess, even in apparently immunocompetent patients. A rapid surgical intervention and standard microbiological procedure help achieve early diagnosis and better therapeutic outcome.
References | |  |
1. | Mamelak AN, Obana WG, Flaherty JF, Rosenblum ML. Nocardial brain abscess: Treatment strategies and factors influencing outcome. Neurosurgery 1994;35:622-31. [PUBMED] [FULLTEXT] |
2. | Saubolle MA, Sussland D. Nocardiosis: Review of clinical and laboratory experience. J Clin Microbiol 2003;41:4497-501. [PUBMED] [FULLTEXT] |
3. | Garrat MA, Holmes HT, Nolte FS. Selective buffered charcoal-yeast extract medium for isolation of nocardiae from mixed cultures. J Clin Microbiol 1992;30:1891-2. |
4. | Singh M, Sandhu RS, Randhawa HS. Comparison of paraffin baiting and conventional culture techniques for isolation of Nocardia asteroides from sputum. J Clin Microbiol 1987;25:176-7. [PUBMED] [FULLTEXT] |
5. | Wauters G, Avesani VR, Charlier J, Janssens M, Vaneechoutte M, Delmιe M. Distribution of nocardia species in clinical samples and their routine rapid identification in the laboratory. J Clin Microbiol 2005;43:2624-8. |
6. | Sorrell TC, Mitchell DH, Iredell JR. Nocardia species. In : Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas and Bennett's Principle and Practice of Infectious Diseases. 6 th ed. Elsevier Churchill Livingstone: Pennsylvania; 2005. p. 2916-24. |
7. | Moylett EH, Pacheco SE, Brown-Elliott BA, Perry TR, Buescher ES, Birmingham MC, et al . Clinical experience with linezolid for the treatment of nocardia infection. Clin Infect Dis 2003;36:313-8. |

Correspondence Address: Prithwiraj Chakrabarti Department of Microbiology, Advanced Medicare Research Institute (AMRI) Hospitals, P-4 and 5, CIT Scheme, Block-A, Gariahat Road, Kolkata - 700 029 India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/0377-4929.40432

[Figure - 1], [Figure - 2] |
|
This article has been cited by | 1 |
Nocardiosis of the Central Nervous System |
|
| Theodora Anagnostou,Marios Arvanitis,Themistoklis K. Kourkoumpetis,Athanasios Desalermos,Herman A. Carneiro,Eleftherios Mylonakis | | Medicine. 2014; 93(1): 19 | | [Pubmed] | [DOI] | | 2 |
49-YEAR-OLD TRANSPLANT RECIPIENT WITH FEVER AND ALTERED MENTAL STATUS |
|
| Arnob K. Mukherjee,Orestes E. Solis,Noriko Salamon,Rupal I. Mehta | | Brain Pathology. 2012; 22(5): 729 | | [Pubmed] | [DOI] | | 3 |
Nocardiosis: Updated Clinical Review and Experience at a Tertiary Center |
|
| J. Ambrosioni, D. Lew, J. Garbino | | Infection. 2010; 38(2): 89 | | [VIEW] | [DOI] | | 4 |
The biocontaminants and complexity of damp indoor spaces: more than what meets the eyes |
|
| Jack D Thrasher,Sandra Crawley | | Toxicology and Industrial Health. 2009; 25(9-10): 583 | | [Pubmed] | [DOI] | | 5 |
The biocontaminants and complexity of damp indoor spaces: More than what meets the eyes |
|
| Thrasher, J.D., Crawley, S. | | Toxicology and Industrial Health. 2009; 25((9-10)): 583-615 | | [Pubmed] | |
|
|
 |
 |
|
|
|
|
|
|
Article Access Statistics | | Viewed | 5422 | | Printed | 140 | | Emailed | 1 | | PDF Downloaded | 315 | | Comments | [Add] | | Cited by others | 5 | |
|

|