Miliary Tuberculosis in a Two-Year-Old Child: A Case Report from a Low-Prevalence Region

Abstract

Background:

Tuberculosis (TB) remains the leading cause of death caused by a single infectious agent.

Objective:

We report a case of miliary TB in a 2-year-old child who presented with a history of constipation, weight loss, marked abdominal distension with hepatosplenomegaly.

Case presentation:

In children, TB often presents with a wide range of non-specific clinical and radiological manifestations, making diagnosis challenging, particularly in regions with low prevalence. We report the case of a two-year-old female with a history of constipation, weight loss, marked abdominal distension with hepatosplenomegaly, who was later diagnosed with miliary tuberculosis.

Conclusion:

This case highlights an unusual presentation of miliary TB in a very young child, a demographic in which it is infrequently observed. Miliary TB remains a severe and potentially fatal condition, particularly when diagnosis and treatment are delayed. The diagnosis is usually made based on the clinical presentation, supported by a classic miliary pattern on chest X-ray.

1. BACKGROUND

Tuberculosis (TB) is a leading cause of preventable morbidity and mortality due to an infectious agent worldwide (1). The World Health Organization reports that around 1.1 million children under the age of 15 develop TB each year, with approximately 226,000 (20.5%) of them succumbing to the disease, indicating its high mortality rate among children (2). The disease primarily affects the lungs but can occasionally spread through the bloodstream, leading to extrapulmonary tuberculosis manifestations such as tuberculosis meningitis and skeletal tuberculosis. In rare cases, systemic dissemination occurs when a Mycobacterium tuberculosis-laden focus enters the vascular system, resulting in a distinct morphological presentation known as miliary tuberculosis (3).

2. OBJECTIVE

We report a case of miliary TB in a 2-year-old child who presented with a history of constipation, weight loss, marked abdominal distension with hepatosplenomegaly, and later diagnosed with miliary tuberculosis.

3. CASE PRESENTATION

A 2-year-old girl of Moroccan origin presented to the hospital with constipation and reduced appetite, symptoms that her parents had noticed for several days. She had grown regularly and received all routine vaccinations before this.

During the initial evaluation in the emergency department, the girl appeared generally well but was slightly underweight. She had no fever, her abdomen was distended but non-tender, with audible bowel sounds. The parents opted to take her home instead of admitting her.

Two weeks later, the patient returned to the emergency department in a more concerning state. Physical examination revealed a body temperature of 36.5°C, pulse rate of 170 beats/min, respiratory rate of 32 breaths/min, and oxygen saturation of 98% breathing room air. Chest auscultation revealed crackles in both lungs, with normal vocal and tactile fremitus. Her abdominal examination revealed marked distension. Bilateral lymphadenopathy was noted in the inguinal and cervical regions, and her arms appeared hypotrophic.

Laboratory tests upon admission showed lymphocytic leukocytosis and elevated inflammatory markers (C-reactive protein: 6.61 mg/dL). She had microcytic hypochromic anemia (hemoglobin: 8.6 g/dL) and severe vitamin D deficiency. The peripheral blood analysis results are summarized in Table 1.

Table 1. Analysis of peripheral blood count upon admission.

White blood cells	14.460/µL
Hemoglobin level	8,6 g/dL
C-reactive protein	6,61 mg/dL
Platelets	597.000/µL
Vitamin D	4.86 ng/mL

Imaging studies included an abdominal ultrasound, which demonstrated ascites and conglomerated bowel loops, along with a chest X-ray that showed consolidation in the right perihilar region (Figure 1).

Figure 1. AP chest X-ray at the time of hospitalization demonstrated an extensive consolidation in the right perihilar region.

A chest and abdominal CT demonstrated large pulmonary lesions and multiple lymphadenopathies (Figure 2).

Figure 2. (A, B) Chest CT scan without contrast: presence of a large lung lesion at the level of the right middle lobe (arrow). Multiple lymphadenopathies in the thoracoabdominal area and some scattered micronodules in a random distribution in both lungs. (C, D) Abdominal CT scan: abundant layer of peritoneal effusion with a compressive effect on the small intestinal loops, peritoneal thickening with multiple attached nodularities.

Given the suspicion of pulmonary and extrapulmonary tuberculosis, the patient underwent further diagnostic tests, including a Mantoux test and Quantiferon, both of which were positive. Gastric aspirates showed negative Ziehl-Neelsen staining, but culture results were positive for Mycobacterium tuberculosis. A lumbar puncture yielded clear, acellular cerebrospinal fluid, with negative microbiological results. The patient was diagnosed with miliary TB.

She was started on a four-drug antitubercular therapy regimen: isoniazid, rifampicin, pyrazinamide, and ethambutol. The patient received supportive care throughout her hospitalization, including oral iron for her anemia and vitamin D supplementation. She remained afebrile throughout her stay. Her clinical status steadily improved, with a notable reduction in abdominal circumference and normalization of inflammatory markers.

After one year of treatment, a follow-up chest X-ray revealed a nodular density in the right upper lobe, consistent with post-tuberculous changes (Figure 3). The patient completed her therapy without adverse reactions and achieved significant improvements in weight and height.

Figure 3. AP chest X-ray at the end of the treatment showed a nodular density in the right upper lobe.

4. DISCUSSION

In this case report, we present evidence of miliary TB in a 2-year-old girl. Miliary TB is more commonly seen in middle-aged and older individuals than in children (4, 5). According to the literature, miliary TB also exhibits a male predominance, with an average age of 43 years (6). In this case, however, the unusual presentation of miliary TB was observed in a young child.

Infants are considerably more likely than immunocompetent older children to develop extrapulmonary tuberculosis (7-9). The crucial event in the development of miliary TB is a massive lymphohematogenous dissemination of Mycobacterium tuberculosis from a pulmonary or extrapulmonary focus, followed by embolization to the vascular beds of various organs.

No uniform guidelines exist for diagnosing miliary TB, but the following criteria have been suggested (10):

• Clinical presentation consistent with a diagnosis of tuberculosis—e.g., pyrexia with an evening rise in temperature, night sweats, anorexia, and weight loss of greater than 6 weeks in duration—responding to anti-tuberculosis treatment.

• Typical miliary pattern on a chest radiograph, and/or bilateral, diffuse reticulonodular lung lesions on a background of miliary shadows demonstrable either on a chest radiograph or high-resolution CT scan.

• Microbiological, histopathological, or molecular evidence of tuberculosis.

The chest radiograph shows typical miliary mottling, characterized by homogeneously distributed, discrete, uniformly sized (1–2 mm), millet-shaped lesions throughout all lung zones. These features are also the radiographic hallmark of miliary TB (11-13). High-resolution CT scans have considerably improved the ante-mortem diagnosis of miliary TB, often revealing the classic miliary pattern even when the chest radiograph appears normal (10).

Miliary tuberculosis is uniformly fatal if not treated (11). The mortality associated with miliary TB is about 15–20% in children (14-18) and 25–30% in adults (19-25). Delays in diagnosis or in the initiation of treatment remain significant contributors to the high mortality rate.

5. CONCLUSION

This case highlights an unusual presentation of miliary TB in a very young child, a demographic in which it is infrequently observed. Miliary TB remains a severe and potentially fatal condition, particularly when diagnosis and treatment are delayed. The diagnosis is usually made based on the clinical presentation, supported by a classic miliary pattern on chest X-ray.

Patient Consent Form:

The patient’s parents gave written informed consent to the publication of this case report and any accompanying images.

Author’s Contribution:

Conceptualization: GD, SC, BV, and FC. Writing–original draft preparation: GD. Writing—review and editing: SC, BV, and FC. All authors have read and agreed to the final version of the manuscript.

Conflicts of interest:

There are no conflicts of interest.

Financial support and sponsorship:

None.