Tuberculous subcutaneous abscess: An analysis of seven cases

Tubercleand LungDisease(1996) 77, 184-187 © 1996 PearsonProfessionalLtd

Case report

Tuberculous subcutaneous abscess: an analysis of seven cases C. H. Chen*, J. F. Shih*, L.-S. Wang *, R. P. Perng*

*Department of Chest Medicine, ?Chest Surgery Section, Department of Surgery, Veterans General HospitalTaipei, Taipei, Taiwan S U M M A R Y. Between 1987 and 1994, seven cases of tuberculous subcutaneous abscesses diagnosed at Veterans General Hospital, Taipei, were studied retrospectively. Three of them had associated underlying medical conditions. Multiple lesions occurred in patients with compromised immune status. Three cases were presented as tumor-like in form, and were tentatively diagnosed as chest wall t u m o r before mycobacterial and pathologic results were available. Except for two cases which received prolonged chemotherapy due to drug side effects or suspected drug resistance, all our cases responded well to 6 to 12 months of current antituberculosis agents. We concluded that (1) it is sometimes difficult to differentiate subcutaneous tuberculous abscess f r o m chest wall t u m o r so physicians should b e a r in mind that tuberculosis could be the cause of such lesion, and that (2) all cases could he treated with a current chemotherapy regimen. Only a small portion of abscess needs repeated aspiration, and surgical incision and excision m a y not be necessary. R/~ S U M/~. Entre 1987 et 1994, sept cas d'abcbs tuberculeux sous-cutan6s diagnostiqu6s au Veterans General Hospital-Taipei ont 6t6 6tudi6s r6trospectivement. Trois d ' e n t r e eux pr6sentaient des 6tats pathologiques associ6s sons-jacents. Des 16sions multiples sont apparues chez des patients ayant un statut immunitaire compromis. Trois cas se sont pr6sent6s sous forme de t u m e n r et furent diagnostiqu6s dans un p r e m i e r temps (/~ titre provisoire) c o m m e t u m e u r de la paroi thoracique avant que les r6snltats mycobact6riens et pathologiques ne fussent obtenus. Except6 p o u r deux cas qul avaient requ une chimioth6rapie prolong6e en raison d'effets secondaires li6s aux m6dicaments ou d ' u n e r6sistance aux m6dicaments soupqonn6e, tousles cas ont bien r6agi /~ une cure de 6/i 12 mois des agents antituberculeux usuels. I I e n a 6t6 conclu que: 1) il est parfois difficile de distinguer un abc/~s tuberculeux sous-cutan6 d ' u n e t u m e u r de la paroi thoracique; aussi les m6decins devraient-ils se rappeler que la tuberculose peut 6tre la cause d ' u n e telle 16sion; et que 2) t o u s l e s cas pourraient 6tre soign6s avec un r6gime chimioth6rapique usuel. Une petite partie de l'abc~s seulement n6cessite une aspiration r6p6t6e et une incision et excision chirurgicales ne sont pas toujours n6cessaires. R E S U M E N. Entre 1987 y 1994, se estudiaron retrospectivamente 7 casos de absceso tuberculoso subcutfineo diagnosticados en el Veterans General Hospital de Taipei. Tres de ellos presentaban una patologia subyacente asociada. Aparecieron lesiones mfiltiples en pacientes con un compromiso del estado inmunitario. Tres casos se presentaron en f o r m a de t u m o r y fueron diagnosticados presuntivamente como t u m o r de la pared, antes de la obtenci6n de los resultados micobacteriol6gicos y anatomopatol6gicos. Exceptuando dos casos que habian recibido una quimioterapia prolongada, debido a efectos secundarios a los medicamentos o p o r sospecha de resistencia a loa medicamentos, todos nuestros casos respondieron bien a esquemas de 6 a 12 meses con los medicamentos antituberculosos habituales. Se conduy6 que: (1) a veces es dificil distinguir un absceso tuberculoso subcutfineo de un t u m o r de la pared, de m a n e r a que los m6dicos tendrian que tener presente que la tuberculosis puede ser la causa de tal tipo de lesiones (2) yodos los casos podrian ser tratados con esquemas terap6uticos habituales. S61o una pequefia proporci6n de abscesos necesita una aspiraci6n repetida y la incisi6n o la excisi6n q u i r f r g i c a s no son siempre necesarias.

differences in the number and virulence of the bacilli, the routes of infection and the host's immunity status, cutaneous tuberculosis occurs in a wide variety of forms. 1 There is no uniform agreement regarding optimal regimens of chemotherapy for cutaneous tuberculosis. For example, some authors have recommended monotherapy

INTRODUCTION Tuberculosis of the skin is a rare disease, accounting for fewer than 1% of all tuberculosis cases seen. Because of Correspondenceto: Dr Chung-HuaChen, Departmentof Chest Medicine, VeteransGeneralHospital, Shih-PalTalpei, Talwan 11217. 184

Tuberculous subcutaneous abscess Table.

185

Patient profiles

Case

Age/sex

Site

WBC

CXR

Size (cm)

Diagnosis

Treatment

Outcome follow-up

Underlying disease

1

69/M

8100

WNL

2x 3x 4

8000

WNL

3x 4x 5

3

32/F

7600

miliary lesions

3.5 x 5

4

56/M

5100 6800

6

27/F

8900

WNL

4x 2x 3

7

69/M

L popliteal fossa R buttock, thighs L chest wall

11300

inactive TB both apex

6x 8x 4

Cure, 5 years cure, 29 months cure, 23 months cure, 5 months

herb dmgs

25/F

active TB both apex WNL

Not recorded

5

R elbow, buttock R index finger, both thighs R elbow, wrist L knee, L hand L chest wall

cure, 23 months cure, 30 months Cure, 45 months

CVA

38/F

Aspiration culture ++++ Aspiration culture ++++ Aspiration culture ++++

11 EHR

2

L anterior chest L buttock

5 x 3 x 5.5

Biopsy culture ++++ Aspiration culture +++ Aspiration culture ++++ Aspiration culture ++++

9 EHR 9 EHRZ/EHR

2 HRZJ4 HR 12 EHR repeat aspiration 4 EHR/11 EHZ + OF 2 EHRZ/9 EHR

none SLE

none SLE none

Abbreviations: WBC = white blood cells; CXR = chest X-ray; CVA = cerebrovascular accident; SLE = systemic lupus erythematosis; R: right, L: left, AFB: acid-fast bacilli, EHR: ethambutol, isoniazid, rifampicin. EHRZ: EHR and pyrazinamide. WNL: within normal limits, OF: ofloxacin.

with isoniazid for lupus vulgaris, tuberculosis verrucosa curls and papulonecrotic tuberculid. However, others have suggested standard triple regimens for prevention of recurrence. 2 Including our previous report, 3 there are only limited case reports on subcutaneous tuberculous abscesses in the English literature. 4 s The optimal treatment of tuberculous skin abscess remain controversial. Some recommended routinely early incision with evacuation of pus and curettage of t h e granulation tissue and necrotic tissue from the abscess cavity. 4 Brown et al and Lantos et al both reported successful triple antituberculosis therapy with isoniazid, rifampin, and ethambutol for 12 months in a single case of subcutaneous tuberculous abscess. 1,s Some did not state the duration of antituberculosis therapyY

MATERIAL AND METHODS Hospital records of seven cases with a definite diagnosis of subcutaneous tuberculous abscess at the Veterans General Hospital-Taipei from January 1987 to December 1994 were obtained and reviewed. The patients had been diagnosed and treated at the Department of Surgery, the Department of Chest Medicine, or in the Infectious Diseases section. In this review, the definition of tuberculous subcutaneous abscess includes the following criteria:

and AFB were demonstrated on pathologic specimens, the surgically excised specimen had not been sent for mycobacterial culture. Thus, the possibility of subcutaneous abscess being caused by mycobacteria other than tuberculosis can not be completely excluded. As a result they were excluded from the analysis.

RESULTS The age of the patients at the time of diagnosis ranged from 25 to 69 years; the average age was 45.1 years. The male to female ratio was 3:4. The underlying diseases observed in our patients included systemic lupus erythematosis (SLE) (two cases) and cerebrovascular accident (CVA) (one case). One case involved a Chinese herb drug user in whom prednisolone intake was suspected. Three patients had no previous adverse medical conditions (Table). Most of our patients presented with a solitary (four cases) or multiple (three cases) bluish-red or brownish painful macules, pustules, indurations or mass-like lesions indistinguishable from skin tumors (Fig. 1). Multiple

1. cutaneous abscess with acid-fast bacilli (AFB) demonstrated on smear and growth of Mycobacterium tuberculosis on culture; 2. because we want to analyse isolated tuberculous subcutaneous abscess only, subcutaneous abscess secondary to underlying tuberculous lymphadenitis (scrofuloderma) and tuberculous empyema with pleurocutaneous fistula were excluded from this study. Only seven patients met the criteria and were included in this study. In a further four cases, although granulomatous inflammation with caseous necrosis, giant cells

Fig. 1--Physical examination showed a bulging mass at the left anterior chest.

186 Tubercleand Lung Disease

A

B Fig. 2--(a) CT scan of Case 7 after administering intravenous contrast medium showeda large anterior chest wall mass with central necrosis and without evidence of rim enhancement. The bony structure was intact. (b) Ultrasonog~aphyof the same case showed nonhomogeneoushypoechoiclesion with posterior echoic enhancement. The case was documentedto be tuberculous abscess by smear and culture of aspirated material.

abscesses occurred in three immunocompromised patients, including two cases with SLE and one with herb drug usage. The size of the lesions, according to medical chart record, measured by computed tomography (CT), ultrasonography or physical examination, ranged from 2 x 3 x 4 c m to 4 x 6 x 8 c m (Fig. 2). Fever and leukocytosis were infrequent but did occur in one case each. Two cases had concomitant active pulmonary tuberculosis: chest X-ray presented miliary nodulation in one and bilateral fibroexudative lesions in the other. One patient was found to have inactive pulmonary tuberculosis. The other four cases had completely normal chest roentgenograms. Except for Case 3, whose skin manifestation was noted during effective treatment for miliary tuberculosis, 3 cutaneous abscess was the initial clinical presentation in the other six cases. Six of the

seven patients were diagnosed by needle aspiration and mycobacteriological culture. Another case who underwent surgical biopsy and pathologic examination disclosed granulomatous inflammation with caseous necrosis, giant cells and existence of AFB. The surgically excised specimen was sent for mycobacterial tissue culture and M. tuberculosis was grown. Three cases received regimens containing ethambutol (E), isoniazid (H), and rifampin (R) for 9 to 12 months. Three cases received EHRZ, with pyrazinamide (Z) in the first few months and the EHR regimen continued for various durations, ranging from 6 to 11 months in total. All of these cases responded to treatment well, and the skin lesions showed no evidence of recurrence during 4 to 60 months of follow-up. Contrary to ordinary guidelines for antituberculosis treatment, Case 3 received pyrazinamide for 9 months because tuberculous subcutaneous abscesses developed during the initial 1--4 months of regular treatment for miliary tuberculosis, and treatment failure was suspected. Pyrazinamide was withdrawn when a susceptibility test showed that mycobacteria were susceptible to all antituberculosis drugs. The lung and skin lesions disappeared after continuous treatment and it was concluded that emergence of tuberculous subcutaneous abscesses during treatment for pulmonary tuberculosis does not necessarily indicate treatment failure? The treatment course of Case 6 also had complications: drug side effects necessitated a brief period of irregular treatment; however, the patient was free of skin lesions after prolonged treatment. The brief clinical course of Case 6 is described as follows. A 27-year-old Taiwanese woman with documented SLE had been on maintenance treatment with prednisolone and hydroxyquinine. She received debridement and skin graft for panniculitis over the left popliteal fossa in November, 1991, and suffered from intermittent fever 5 months later. On examination, multiple subcutaneous nodules, the largest 6 x 4 cm in size, were found at the inner aspect of both thighs. The peripheral white cell count was 8.9 x 109/1 with 77% polymorphs and 17% lymphocytes. Gallium scan revealed inflammatory processes over the right arm, the right supraclavicular soft tissue, both thighs and the left calf. M. tuberculosis was cultured from pus yielded by ultrasonically guided needle aspiration from the subcutaneous abscesses of both thighs. She began a regimen of ethambutol, rifampin and isoniazid on 14 April 1992. Drugs were withheld for 4 weeks because of rifampin-induced fever after 2 months of therapy. On 6 June rifampin was discontinued and streptomycin 750 mg, ofloxacin 800 mg, and pyrazinamide 1500 mg daily were added. Streptomycin was discontinued 2 weeks later because of a painful sensation over the injection site. The skin lesions did not improve smoothly and new lesions were observed during treatment. Repeated aspiration of pus was required from both thighs, right knee, right popliteal fossa and right supraclavicular area. Because of uneven clinical responses, she received a total of 15 months of antituberculosis treatment.

Tuberculous subcutaneous abscess

DISCUSSION Cutaneous tuberculous abscesses can occur due to: 1. extension of an embolism of organisms to subcutaneous tissue from pulmonary foci; 2. direct skin inoculation; and 3. extension from an underlying lymphadenitis, synovitis or osteomyelitis. Some cases of isolated subcutaneous tuberculous infection have been reported as a complication of intramuscular penicillin injection, and two pathogeneses were postulated: 1. subcutaneous inoculation from contaminated instrument or medication, or 2. the injection itself may have damaged the subcutaneous tissue so that organisms, dormant elsewhere, lodged in these areas of diminished resistance. 6,7 Because normal roentgenographic findings can not exclude the possibility of tuberculous infection, current tuberculosis or previous episodes of tuberculosis, 9 a previous tuberculous infection or latent tuberculosis cannot be excluded in the four cases of the present series with normal chest roentgenographic findings. Thus, cutaneous tuberculosis in all of our cases may represent direct extension from an infected pulmonary or extrapulmonary focus via hematogenous or lymphatic spread. Altering local susceptibility may be another explanation for Case 6 who had a previous history of debridement and skin graft for panniculitis. Other cases denied any history of skin injury, and the possibility of direct inoculation may be low. Reduced local or systemic cellular immunity due to an underlying medical condition also contributed to the development of subcutaneous tuberculous abscesses in three of these cases. The skin presentation may be confused with other diseases such as neoplasm. Three of our cases were tentatively diagnosed as chest wall mass initially. All these cases received chest CT scan revealing chest wall mass with low attenuated central area without rim enhancement (Fig. 2a), in contrast to the report by Adler et al who reported that tuberculosis of the chest wall was characterized by bone and costal cartilage destruction, soft tissue mass with calcification or rim enhancement with or without evidence of underlying lung or pleural disease. 1° Because of the advantages of ultrasonographic examination: 1. no radiation is required; 2. the procedure can be performed at the patient's bedside; 3. in the case of a large lesion (specimens can be obtained from different regions of the lesion which show different echogenicity), it is used on peripheral lung, pleural or chest wall lesions. Ultrasonography of two of our cases showed subcutaneous hypoechoic lesion with posterior echoic enhancement and pus was obtained successfully under ultrasonic

187

guidance. There are no reports of ultrasonographic examination of tuberculous subcutaneous abscess in the literature. It is difficult to differentiate tuberculous subcutaneous abscess from chest wall tumors by CT scan or ultrasonography. Maintaining a high degree of suspicion is mandatory and mycobacterial studies (including smear, culture and susceptibility tests) are important for specimens obtained from aspiration or biopsy, especially in endemic areas. Four cases with histologic diagnosis of granulomatous inflammation were positive microscopically for AFB and responded well to antituberculosis treatment. They were excluded from this analysis because infection caused by atypical tuberculosis could not be completely excluded. With advances in modem chemotherapy, tuberculosis can be treated with a 6-month regimen consisting of HRZ given for 2 months, followed by HR for 4 months, or a 9-month regimen of HR. These regimens are highly effective even for an immunocompromised host or for some extrapulmonary tuberculoses. 11 In Taiwan, the recommended treatment for extrapulmonary tuberculosis was HERZ given for 2 months, followed by HRE for 10 months. Because of the limited number of case reports of tuberculous skin abscesses available, optimal treatment has still not been determined. Although repeated aspiration to prevent reaccumulation of pus and prolonged chemotherapy due to drug side-effects or delayed susceptibility test reports were necessary in two of our cases, other cases responded well to various durations (6-12 months) of current chemotherapy regimens. We conclude that current chemotherapy for tuberculous subcutaneous abscess is optimal. Surgical incision or excision may not be necessary and should be reserved for the purpose of obtaining specimens for definite diagnosis.

References 1. Brown T S, Anderson R H, Burnett J W. Cutaneous tuberculosis. J A m Acad Dermatol 1982; 6: 101-106. 2. Ramesh V, Misra R S, Saxena U, Mukherjee. Comparative efficacy of drug regimens in skin tuberculosis. Clinical Experimental Dermatology 1991; 16: 106-109. 3. Chen C H, Tsai J J, Shih J F, Perng R P. Tuberculous subcutaneous abscesses developing during chemotherapy for pulmonary tuberculosis. Scand J Infect Dis 1993; 25: 149-152. 4. Shaw N M, Basu A K. Unusual cold abscesses. Br J Surg 1970; 57: 418-422. 5. Kounis N G, Constantinidis K. Unusual tuberculous skin manifestations. Practitioner 1979; 222: 390-393. 6. Forbes G B, Strange F G S. Tuberculous abscess at the site of penicillin injections. Lancet 1949; 1: 478. 7. Glynn K P. Isolated subcutaneous abscess caused by Mycobacterium tuberculosis. Am Rev Respir Dis 1969; 99: 86-88. 8. Lantos G, Fisher B K, Contreras M. Tuberculosis ulcer of the skin. J A m Academy Derma 1988; 6: 1067-1072. 9. American Thoracic Society. Diagnostic standards and classification of tuberculosis and other mycobacterial diseases. Am Rev Respir Dis 1981; 123: 343-55. 10. Adler B D, Padley S P G, Muller N L. Tuberculosis of the chest wall: CT findings. J Comput Assist Tomograph 1993; 17: 271-273. 11. Dutt A K, Moers D, Stead W W. Short-course chemotherapy for extrapulmonary tuberculosis - nine years' experience. Ann Int Med 1986; 104: 7-12.