1. Destructive rib lesions in an HIV sero-negative male: An unusual presentation of TB
Lydia Nakiyingi1, John M Bwanika, Bruce Kirenga, Robert Lukande, Tom P Mwambu, William Worodria, Martin Okot-Nwang
1Physician, Mulago Hospital, Pulmonology Unit

2. Introduction
TB incidence remains high in developing countries and diagnosis poses a big challenge for health care providers.
15-20 % of all TB cases are EPTB, skeletal TB is an uncommon form of EPTB (0.1% of TB cases)
TB of the rib or rib cage is a very rare form of skeletal TB
TB rib diagnosis may be difficult
a low index suspicion by clinicians.
presentation often mimics malignant disease clinically and radiologically
diagnosis only confirmed by tissue biopsy
Results into delayed or missed diagnosis with subsequent devastating deformities and functional deficits.

3. Case summary A 32 YO male hospital worker admitted to Mulago
Hospital with:
3 mos h/o of progressively worsening Rt pleuritic chest pain, weight loss, fatigue, anorexia and low-grade fever with night sweats.
He had had a dry cough 2 mos prior to admission which subsided a wk later after taking oral abcs.
No subsequent cough, sputum production or haemoptysis at presentation

4. Case summary cont. Denied a h/o of previous TB
Had not received BCG vaccination as a child.
No chronic illness and no history of smoking, alcohol consumption or drug abuse.
Physical exam
Wasted but was afebrile.
Chest movement was minimal because of pain in the right chest.
Tenderness to palpation over the right axillary area but no swelling.
Auscultation revealed a pleural rub.
Rest of the clinical exam was unremarkable.

5. Investigations Neg HIV antibody test, Normal CBC
Normal serum biochemistries (LFTs, RFTs, electrolytes)
Neg aerobic blood cultures.
Raised C-reactive protein (42.39mg/L)
High ESR (110mm/hr, Westergren method).
A ZN sputum smear was neg for AFBs.

6. CXR- PA
Wedge opacity arising from the pleura in the right mid-lung zone

7. Chest Ultrasound scan
Confirmed a cystic mass (4.3cm by 2.7cm) containing echogenic mobile structures in the right pleural space with normal adjacent tissue.
Purulent material on aspiration of the cystic mass
Negative Gram’s stain,
Negative ZN stain
Negative aerobic culture.
Cytological exam was negative for malignancy.

8. Chest CT scan
A chest CT scan of the patient showing a mass in the right fourth intercostal space extending to the pleura with 4th rib destruction (arrow)

9. Chest CT
A chest CT scan showed a fusiform-shaped mass (4.8cm by 2.7cm) in the right fourth intercostal space extending to the pleura with destructive lesions in the right 4th and 7th ribs. No pulmonary lesions were seen.

10. Differential Diagnosis
Malignant lytic bone lesions
Multiple Myeloma
Metastatic disease
Lymphoma
Benign inflammatory condition acute-on-chronic process
Complicated by a chest wall abscess/necrosis. Antibiotics (IV) were administered.

11. Further Invx
Serum protein electrophoresis and Bence Jones proteins were negative
The patient underwent surgery for biopsy and drainage:
A cystic mass (3cm by 10cm) in the right 4th intercostal space, extending to the pleura with destruction of the 4th rib and caseous necrosis in the underlying soft tissue.
En block resection of the cystic mass together with rib resection was done
A cut section of the mass revealed a purulent discharge with macroscopic caseation of the underlying soft tissue

12. A B C
Surgical specimen showing a resected section of the rib and the affected soft tissue (B) and caseation (arrow) that was revealed on dissection of the same surgical specimen (C)

13. Histo-pathological examB C
Microscopic examination of the tissue biopsy showing; granulomatous lesions (A-i, ii, iii), giant cell (B, arrow) and bone necrosis (C).

14. Diagnosis & Rx
TB of the rib cage involving the 4th and 7th ribs with ‘cold abscess’.
The patient was put on antiTB Rx (new case); 2HERZ/6RH.
He recovered well post-operatively and was still doing well on follow up at 6 mos.

15. Learning points
TB of the rib must be considered in patients with destructive rib lesions in high TB endemic regions
A high index of suspicion may prevent delayed/missed diagnosis
Lack of clinical and radiological evidence of pulm involvement does not rule out skeletal TB
Clinical and radiological findings in rib TB may be indistinguishable from malignant disease
Definitive diagnosis of Rib Tb requires surgical intervention which is both diagnostic & therapeutic

16. Acknowledgment Staff on ward 4C pulmonology unit
Staff on cardiothoracic ward, UHI
Pathology & Radiology Depts,MUCHS
IDI, MUCHS, research Dept
The patient for permission to present